298458: Add Java 5 Generics to the p2 code base

50 files changed, 453 insertions, 496 deletions

diff --git a/bundles/org.eclipse.equinox.p2.ql/.classpath b/bundles/org.eclipse.equinox.p2.ql/.classpath
index 2fbb7a23e..64c5e31b7 100644
--- a/bundles/org.eclipse.equinox.p2.ql/.classpath
+++ b/bundles/org.eclipse.equinox.p2.ql/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.4"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="output" path="bin"/>
diff --git a/bundles/org.eclipse.equinox.p2.ql/.settings/org.eclipse.jdt.core.prefs b/bundles/org.eclipse.equinox.p2.ql/.settings/org.eclipse.jdt.core.prefs
index c8a5bb1a1..3801a0f64 100644
--- a/bundles/org.eclipse.equinox.p2.ql/.settings/org.eclipse.jdt.core.prefs
+++ b/bundles/org.eclipse.equinox.p2.ql/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Sun Dec 06 23:10:54 EST 2009
+#Tue Dec 22 17:40:14 CET 2009
 eclipse.preferences.version=1
 org.eclipse.jdt.core.builder.cleanOutputFolder=clean
 org.eclipse.jdt.core.builder.duplicateResourceTask=warning
@@ -7,17 +7,17 @@ org.eclipse.jdt.core.builder.resourceCopyExclusionFilter=*.launch
 org.eclipse.jdt.core.circularClasspath=error
 org.eclipse.jdt.core.classpath.exclusionPatterns=enabled
 org.eclipse.jdt.core.classpath.multipleOutputLocations=enabled
-org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=disabled
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.2
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.5
 org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
-org.eclipse.jdt.core.compiler.compliance=1.4
+org.eclipse.jdt.core.compiler.compliance=1.5
 org.eclipse.jdt.core.compiler.debug.lineNumber=generate
 org.eclipse.jdt.core.compiler.debug.localVariable=generate
 org.eclipse.jdt.core.compiler.debug.sourceFile=generate
 org.eclipse.jdt.core.compiler.doc.comment.support=enabled
 org.eclipse.jdt.core.compiler.maxProblemPerUnit=1000
 org.eclipse.jdt.core.compiler.problem.annotationSuperInterface=warning
-org.eclipse.jdt.core.compiler.problem.assertIdentifier=warning
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
 org.eclipse.jdt.core.compiler.problem.autoboxing=ignore
 org.eclipse.jdt.core.compiler.problem.comparingIdentical=warning
 org.eclipse.jdt.core.compiler.problem.deadCode=warning
@@ -26,7 +26,7 @@ org.eclipse.jdt.core.compiler.problem.deprecationInDeprecatedCode=disabled
 org.eclipse.jdt.core.compiler.problem.deprecationWhenOverridingDeprecatedMethod=enabled
 org.eclipse.jdt.core.compiler.problem.discouragedReference=warning
 org.eclipse.jdt.core.compiler.problem.emptyStatement=warning
-org.eclipse.jdt.core.compiler.problem.enumIdentifier=warning
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
 org.eclipse.jdt.core.compiler.problem.fallthroughCase=ignore
 org.eclipse.jdt.core.compiler.problem.fatalOptionalError=enabled
 org.eclipse.jdt.core.compiler.problem.fieldHiding=warning
@@ -89,7 +89,7 @@ org.eclipse.jdt.core.compiler.problem.unusedParameterWhenOverridingConcrete=enab
 org.eclipse.jdt.core.compiler.problem.unusedPrivateMember=error
 org.eclipse.jdt.core.compiler.problem.unusedWarningToken=warning
 org.eclipse.jdt.core.compiler.problem.varargsArgumentNeedCast=warning
-org.eclipse.jdt.core.compiler.source=1.3
+org.eclipse.jdt.core.compiler.source=1.5
 org.eclipse.jdt.core.formatter.align_type_members_on_columns=false
 org.eclipse.jdt.core.formatter.alignment_for_arguments_in_allocation_expression=16
 org.eclipse.jdt.core.formatter.alignment_for_arguments_in_enum_constant=16
diff --git a/bundles/org.eclipse.equinox.p2.ql/META-INF/MANIFEST.MF b/bundles/org.eclipse.equinox.p2.ql/META-INF/MANIFEST.MF
index 946ba908c..d846f2a90 100644
--- a/bundles/org.eclipse.equinox.p2.ql/META-INF/MANIFEST.MF
+++ b/bundles/org.eclipse.equinox.p2.ql/META-INF/MANIFEST.MF
@@ -6,15 +6,18 @@ Bundle-Version: 1.0.0.qualifier
 Bundle-ClassPath: .
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
-Bundle-RequiredExecutionEnvironment: J2SE-1.4,
+Bundle-RequiredExecutionEnvironment: J2SE-1.5,
+ J2SE-1.4,
  CDC-1.1/Foundation-1.1
 Bundle-ActivationPolicy: lazy
-Import-Package: org.eclipse.equinox.internal.p2.metadata,
+Import-Package: org.eclipse.equinox.internal.p2.core.helpers,
+ org.eclipse.equinox.internal.p2.metadata,
  org.eclipse.equinox.internal.provisional.p2.metadata,
  org.eclipse.equinox.internal.provisional.p2.metadata.query,
  org.eclipse.equinox.p2.metadata,
  org.eclipse.equinox.p2.metadata.query,
  org.eclipse.equinox.p2.repository.artifact,
+ org.eclipse.osgi.service.localization,
  org.osgi.framework
 Export-Package: org.eclipse.equinox.internal.p2.ql.expression;x-internal:=true,
  org.eclipse.equinox.p2.ql
diff --git a/bundles/org.eclipse.equinox.p2.ql/build.properties b/bundles/org.eclipse.equinox.p2.ql/build.properties
index 230777f9a..d6f73676c 100644
--- a/bundles/org.eclipse.equinox.p2.ql/build.properties
+++ b/bundles/org.eclipse.equinox.p2.ql/build.properties
@@ -2,7 +2,7 @@
 # <copyright>
 # </copyright>
 #
-# $Id$
+# $Id: build.properties,v 1.1 2009/12/01 17:41:31 helindbe Exp $
 
 bin.includes = .,\
                META-INF/,\
@@ -13,3 +13,5 @@ source.. = src/
 output.. = bin/
 src.includes = about.html,\
                model/
+javacTarget=jsr14
+javacSource=1.5
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/CapabilityIndex.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/CapabilityIndex.java
index f39aa62f8..fd32fbf9b 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/CapabilityIndex.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/CapabilityIndex.java
@@ -11,9 +11,11 @@
 package org.eclipse.equinox.internal.p2.ql;
 
 import java.util.*;
+import org.eclipse.equinox.internal.p2.core.helpers.CollectionUtils;
 import org.eclipse.equinox.internal.p2.metadata.IRequiredCapability;
 import org.eclipse.equinox.internal.provisional.p2.metadata.IProvidedCapability;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
+import org.eclipse.equinox.p2.metadata.IRequirement;
 import org.eclipse.equinox.p2.ql.ICapabilityIndex;
 
 /**
@@ -21,7 +23,7 @@ import org.eclipse.equinox.p2.ql.ICapabilityIndex;
  */
 public class CapabilityIndex implements ICapabilityIndex {
 
-	private final Map capabilityMap;
+	private final Map<String, Object> capabilityMap;
 
 	private static class IUCapability {
 		final IInstallableUnit iu;
@@ -33,24 +35,24 @@ public class CapabilityIndex implements ICapabilityIndex {
 		}
 	}
 
-	public CapabilityIndex(Iterator itor) {
-		HashMap index = new HashMap();
+	public CapabilityIndex(Iterator<IInstallableUnit> itor) {
+		HashMap<String, Object> index = new HashMap<String, Object>();
 		while (itor.hasNext()) {
-			IInstallableUnit iu = (IInstallableUnit) itor.next();
-			IProvidedCapability[] pcs = iu.getProvidedCapabilities();
-			int idx = pcs.length;
+			IInstallableUnit iu = itor.next();
+			List<IProvidedCapability> pcs = iu.getProvidedCapabilities();
+			int idx = pcs.size();
 			while (--idx >= 0) {
-				IProvidedCapability pc = pcs[idx];
+				IProvidedCapability pc = pcs.get(idx);
 				IUCapability iuCap = new IUCapability(iu, pc);
 				String name = pc.getName();
 				Object prev = index.put(name, iuCap);
 				if (prev != null) {
-					ArrayList lst;
-					if (prev instanceof ArrayList)
-						lst = (ArrayList) prev;
+					ArrayList<IUCapability> lst;
+					if (prev instanceof ArrayList<?>)
+						lst = (ArrayList<IUCapability>) prev;
 					else {
-						lst = new ArrayList(4);
-						lst.add(prev);
+						lst = new ArrayList<IUCapability>(4);
+						lst.add((IUCapability) prev);
 					}
 					lst.add(iuCap);
 					index.put(name, lst);
@@ -60,84 +62,82 @@ public class CapabilityIndex implements ICapabilityIndex {
 		this.capabilityMap = index;
 	}
 
-	public Iterator satisfiesAny(Iterator requirements) {
+	public Iterator<IInstallableUnit> satisfiesAny(Iterator<IRequirement> requirements) {
 		if (!requirements.hasNext())
-			return Collections.EMPTY_LIST.iterator();
+			return CollectionUtils.<IInstallableUnit> emptyList().iterator();
 
-		List collector = new ArrayList();
+		List<IInstallableUnit> collector = new ArrayList<IInstallableUnit>();
 		do {
-			Object nxt = requirements.next();
-			if (!(nxt instanceof IRequiredCapability))
-				throw new IllegalArgumentException();
+			IRequirement nxt = requirements.next();
 			collectMatchingIUs((IRequiredCapability) nxt, collector);
 		} while (requirements.hasNext());
 		return collector.iterator();
 	}
 
-	public Iterator satisfiesAll(Iterator requirements) {
+	public Iterator<IInstallableUnit> satisfiesAll(Iterator<IRequirement> requirements) {
 		if (!requirements.hasNext())
-			return Collections.EMPTY_LIST.iterator();
-
-		Set collector = new HashSet();
-		Object nxt = requirements.next();
-		if (!(nxt instanceof IRequiredCapability))
-			throw new IllegalArgumentException();
-		collectMatchingIUs((IRequiredCapability) nxt, collector);
-
-		while (requirements.hasNext() && !collector.isEmpty()) {
-			nxt = requirements.next();
-			if (!(nxt instanceof IRequiredCapability))
-				throw new IllegalArgumentException();
-			collector = retainMatchingIUs((IRequiredCapability) nxt, collector);
-		}
+			return CollectionUtils.<IInstallableUnit> emptyList().iterator();
+
+		Set<IInstallableUnit> collector = new HashSet<IInstallableUnit>();
+		collectMatchingIUs(requirements.next(), collector);
+
+		while (requirements.hasNext() && !collector.isEmpty())
+			collector = retainMatchingIUs(requirements.next(), collector);
 		return collector.iterator();
 	}
 
-	private void collectMatchingIUs(IRequiredCapability rc, Collection collector) {
+	private void collectMatchingIUs(IRequirement requirement, Collection<IInstallableUnit> collector) {
+		if (!(requirement instanceof IRequiredCapability))
+			return;
+		IRequiredCapability rc = (IRequiredCapability) requirement;
 		Object v = capabilityMap.get(rc.getName());
 		if (v == null)
 			return;
 
 		if (v instanceof IUCapability) {
 			IUCapability iuc = (IUCapability) v;
-			if (rc.satisfiedBy(iuc.capability))
+			if (iuc.capability.satisfies(requirement))
 				collector.add(iuc.iu);
 		} else {
-			List iucs = (List) v;
+			List<IUCapability> iucs = (List<IUCapability>) v;
 			int idx = iucs.size();
 			while (--idx >= 0) {
-				IUCapability iuc = (IUCapability) iucs.get(idx);
-				if (rc.satisfiedBy(iuc.capability))
+				IUCapability iuc = iucs.get(idx);
+				if (iuc.capability.satisfies(requirement))
 					collector.add(iuc.iu);
 			}
 		}
 	}
 
-	private Set retainMatchingIUs(IRequiredCapability rc, Set collector) {
+	private Set<IInstallableUnit> retainMatchingIUs(IRequirement requirement, Set<IInstallableUnit> collector) {
+		if (!(requirement instanceof IRequiredCapability))
+			return CollectionUtils.emptySet();
+
+		IRequiredCapability rc = (IRequiredCapability) requirement;
 		Object v = capabilityMap.get(rc.getName());
 		if (v == null)
-			return Collections.EMPTY_SET;
+			return CollectionUtils.emptySet();
 
-		Set retained = null;
+		Set<IInstallableUnit> retained = null;
 		if (v instanceof IUCapability) {
 			IUCapability iuc = (IUCapability) v;
-			if (rc.satisfiedBy(iuc.capability) && collector.contains(iuc.iu)) {
+			if (iuc.capability.satisfies(requirement) && collector.contains(iuc.iu)) {
 				if (retained == null)
-					retained = new HashSet();
+					retained = new HashSet<IInstallableUnit>();
 				retained.add(iuc.iu);
 			}
 		} else {
-			List iucs = (List) v;
+			List<IUCapability> iucs = (List<IUCapability>) v;
 			int idx = iucs.size();
 			while (--idx >= 0) {
-				IUCapability iuc = (IUCapability) iucs.get(idx);
-				if (rc.satisfiedBy(iuc.capability) && collector.contains(iuc.iu)) {
+				IUCapability iuc = iucs.get(idx);
+				if (iuc.capability.satisfies(requirement) && collector.contains(iuc.iu)) {
 					if (retained == null)
-						retained = new HashSet();
+						retained = new HashSet<IInstallableUnit>();
 					retained.add(iuc.iu);
 				}
 			}
 		}
-		return retained == null ? Collections.EMPTY_SET : retained;
+		return retained == null ? CollectionUtils.<IInstallableUnit> emptySet() : retained;
 	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/Everything.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/Everything.java
index 382e9038b..4f3fc819b 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/Everything.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/Everything.java
@@ -10,48 +10,50 @@
  *******************************************************************************/
 package org.eclipse.equinox.internal.p2.ql;
 
-import java.util.*;
+import java.util.Collection;
+import java.util.Iterator;
+import org.eclipse.equinox.internal.p2.core.helpers.CollectionUtils;
 
 /**
  * The immutable context used when evaluating an expression.
  */
-public final class Everything extends MatchIteratorFilter implements IRepeatableIterator {
+public final class Everything<T> extends MatchIteratorFilter<T> implements IRepeatableIterator<T> {
 	private boolean atStart = true;
 
-	private final Class elementClass;
+	private final Class<T> elementClass;
 
-	public Everything(Class elementClass, Collection collection) {
-		super(RepeatableIterator.create(collection == null ? Collections.EMPTY_LIST : collection));
+	public Everything(Class<T> elementClass, Collection<T> collection) {
+		super(RepeatableIterator.<T> create(collection == null ? CollectionUtils.<T> emptyList() : collection));
 		this.elementClass = elementClass;
 	}
 
-	public Everything(Class elementClass, Iterator iterator, boolean needsRepeat) {
+	public Everything(Class<T> elementClass, Iterator<? extends T> iterator, boolean needsRepeat) {
 		super(needsRepeat ? RepeatableIterator.create(iterator) : iterator);
 		this.elementClass = elementClass;
 	}
 
-	public IRepeatableIterator getCopy() {
-		Iterator iterator = getInnerIterator();
-		if (iterator instanceof IRepeatableIterator)
-			return new Everything(elementClass, ((IRepeatableIterator) iterator).getCopy(), false);
+	public IRepeatableIterator<T> getCopy() {
+		Iterator<? extends T> iterator = getInnerIterator();
+		if (iterator instanceof IRepeatableIterator<?>)
+			return new Everything<T>(elementClass, ((IRepeatableIterator<? extends T>) iterator).getCopy(), false);
 		if (atStart)
 			return this;
 		throw new UnsupportedOperationException();
 	}
 
-	public Object next() {
+	public T next() {
 		atStart = false;
 		return super.next();
 	}
 
 	public Object getIteratorProvider() {
-		Iterator iterator = getInnerIterator();
-		if (iterator instanceof IRepeatableIterator)
-			return ((IRepeatableIterator) iterator).getIteratorProvider();
+		Iterator<? extends T> iterator = getInnerIterator();
+		if (iterator instanceof IRepeatableIterator<?>)
+			return ((IRepeatableIterator<?>) iterator).getIteratorProvider();
 		return this;
 	}
 
-	protected boolean isMatch(Object val) {
+	protected boolean isMatch(T val) {
 		return elementClass.isInstance(val);
 	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/FlattenIterator.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/FlattenIterator.java
index e2d659bb1..f41e20c1b 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/FlattenIterator.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/FlattenIterator.java
@@ -18,14 +18,14 @@ import java.util.NoSuchElementException;
  * elements that can be represented as iterators. The elements of those iterators
  * will be returned in sequence, thus removing one iterator dimension.
  */
-public class FlattenIterator implements Iterator {
+public class FlattenIterator<T> implements Iterator<T> {
 	private static final Object NO_ELEMENT = new Object();
-	private final Iterator iteratorIterator;
-	private Iterator currentIterator;
+	private final Iterator<? extends Object> iteratorIterator;
+	private Iterator<T> currentIterator;
 
-	private Object nextObject = NO_ELEMENT;
+	private T nextObject = noElement();
 
-	public FlattenIterator(Iterator iterator) {
+	public FlattenIterator(Iterator<? extends Object> iterator) {
 		this.iteratorIterator = iterator;
 	}
 
@@ -33,12 +33,12 @@ public class FlattenIterator implements Iterator {
 		return positionNext();
 	}
 
-	public Object next() {
+	public T next() {
 		if (!positionNext())
 			throw new NoSuchElementException();
 
-		Object nxt = nextObject;
-		nextObject = NO_ELEMENT;
+		T nxt = nextObject;
+		nextObject = noElement();
 		return nxt;
 	}
 
@@ -46,6 +46,7 @@ public class FlattenIterator implements Iterator {
 		throw new UnsupportedOperationException();
 	}
 
+	@SuppressWarnings("unchecked")
 	private boolean positionNext() {
 		if (nextObject != NO_ELEMENT)
 			return true;
@@ -55,9 +56,14 @@ public class FlattenIterator implements Iterator {
 				return false;
 
 			Object nextItor = iteratorIterator.next();
-			currentIterator = (nextItor instanceof Iterator) ? (Iterator) nextItor : RepeatableIterator.create(nextItor);
+			currentIterator = (nextItor instanceof Iterator<?>) ? (Iterator<T>) nextItor : RepeatableIterator.<T> create(nextItor);
 		}
 		nextObject = currentIterator.next();
 		return true;
 	}
+
+	@SuppressWarnings("unchecked")
+	private static <T> T noElement() {
+		return (T) NO_ELEMENT;
+	}
 }
\ No newline at end of file
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/IRepeatableIterator.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/IRepeatableIterator.java
index 7190c241f..1f8fa8655 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/IRepeatableIterator.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/IRepeatableIterator.java
@@ -12,14 +12,14 @@ package org.eclipse.equinox.internal.p2.ql;
 
 import java.util.Iterator;
 
-public interface IRepeatableIterator extends Iterator {
+public interface IRepeatableIterator<T> extends Iterator<T> {
 	/**
 	 * Returns a copy that will iterate over the same elements
 	 * as this iterator. The contents or position of this iterator
 	 * is left unchanged. 
 	 * @return A re-initialized copy of this iterator.
 	 */
-	IRepeatableIterator getCopy();
+	IRepeatableIterator<T> getCopy();
 
 	Object getIteratorProvider();
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/MatchIteratorFilter.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/MatchIteratorFilter.java
index 684fdc5ab..1f7b00d2a 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/MatchIteratorFilter.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/MatchIteratorFilter.java
@@ -16,14 +16,14 @@ import java.util.NoSuchElementException;
 /**
  * An iterator filter using a boolean {@link #isMatch(Object)} method.
  */
-public abstract class MatchIteratorFilter implements Iterator {
+public abstract class MatchIteratorFilter<T> implements Iterator<T> {
 	private static final Object NO_ELEMENT = new Object();
 
-	private final Iterator innerIterator;
+	private final Iterator<? extends T> innerIterator;
 
-	private Object nextObject = NO_ELEMENT;
+	private T nextObject = noElement();
 
-	public MatchIteratorFilter(Iterator iterator) {
+	public MatchIteratorFilter(Iterator<? extends T> iterator) {
 		this.innerIterator = iterator;
 	}
 
@@ -31,12 +31,12 @@ public abstract class MatchIteratorFilter implements Iterator {
 		return positionNext();
 	}
 
-	public Object next() {
+	public T next() {
 		if (!positionNext())
 			throw new NoSuchElementException();
 
-		Object nxt = nextObject;
-		nextObject = NO_ELEMENT;
+		T nxt = nextObject;
+		nextObject = noElement();
 		return nxt;
 	}
 
@@ -44,18 +44,18 @@ public abstract class MatchIteratorFilter implements Iterator {
 		throw new UnsupportedOperationException();
 	}
 
-	protected Iterator getInnerIterator() {
+	protected Iterator<? extends T> getInnerIterator() {
 		return innerIterator;
 	}
 
-	protected abstract boolean isMatch(Object val);
+	protected abstract boolean isMatch(T val);
 
 	private boolean positionNext() {
 		if (nextObject != NO_ELEMENT)
 			return true;
 
 		while (innerIterator.hasNext()) {
-			Object nxt = innerIterator.next();
+			T nxt = innerIterator.next();
 			if (isMatch(nxt)) {
 				nextObject = nxt;
 				return true;
@@ -63,4 +63,9 @@ public abstract class MatchIteratorFilter implements Iterator {
 		}
 		return false;
 	}
+
+	@SuppressWarnings("unchecked")
+	private static <T> T noElement() {
+		return (T) NO_ELEMENT;
+	}
 }
\ No newline at end of file
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/ParameterContext.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/ParameterContext.java
index db16a17ed..653c103ad 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/ParameterContext.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/ParameterContext.java
@@ -31,7 +31,7 @@ public final class ParameterContext implements IEvaluationContext {
 	}
 
 	public Object getParameter(String key) {
-		return parameters.length == 1 && parameters[0] instanceof Map ? ((Map) parameters[0]).get(key) : null;
+		return parameters.length == 1 && parameters[0] instanceof Map<?, ?> ? ((Map<?, ?>) parameters[0]).get(key) : null;
 	}
 
 	public Object getValue(IExpression variable) {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/QueryContext.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/QueryContext.java
index 3d7b5b703..adf2393fa 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/QueryContext.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/QueryContext.java
@@ -3,49 +3,58 @@ package org.eclipse.equinox.internal.p2.ql;
 import java.util.*;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.NullProgressMonitor;
-import org.eclipse.equinox.internal.provisional.p2.metadata.query.*;
+import org.eclipse.equinox.internal.provisional.p2.metadata.query.ContextQuery;
+import org.eclipse.equinox.internal.provisional.p2.metadata.query.IQueryable;
+import org.eclipse.equinox.p2.metadata.IInstallableUnit;
 import org.eclipse.equinox.p2.metadata.query.IQuery;
 import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 import org.eclipse.equinox.p2.ql.IQueryContext;
 import org.eclipse.equinox.p2.ql.ITranslationSupport;
+import org.eclipse.osgi.service.localization.LocaleProvider;
 
-public class QueryContext implements IQueryContext {
+public class QueryContext<T> implements IQueryContext<T> {
 
-	private final IQueryable queryable;
+	private final IQueryable<T> queryable;
 
-	private Map translationSupports;
+	private Map<Locale, TranslationSupport> translationSupports;
 
-	public QueryContext(IQueryable queryable) {
+	public QueryContext(IQueryable<T> queryable) {
 		this.queryable = queryable;
 	}
 
-	public QueryContext(Iterator iterator) {
-		final IRepeatableIterator repeatable = RepeatableIterator.create(iterator);
-		this.queryable = new IQueryable() {
-			public IQueryResult query(IQuery query, IProgressMonitor monitor) {
+	public QueryContext(Iterator<T> iterator) {
+		final IRepeatableIterator<T> repeatable = RepeatableIterator.create(iterator);
+		this.queryable = new IQueryable<T>() {
+			public IQueryResult<T> query(IQuery<T> query, IProgressMonitor monitor) {
 				return query.perform(repeatable.getCopy());
 			}
 		};
 	}
 
-	public synchronized ITranslationSupport getTranslationSupport(Locale locale) {
+	public synchronized ITranslationSupport getTranslationSupport(final Locale locale) {
 		if (translationSupports == null)
-			translationSupports = new HashMap();
+			translationSupports = new HashMap<Locale, TranslationSupport>();
 
-		TranslationSupport ts = (TranslationSupport) translationSupports.get(locale);
+		TranslationSupport ts = translationSupports.get(locale);
 		if (ts == null) {
 			ts = new TranslationSupport();
-			ts.setTranslationSource(queryable);
-			ts.setLocale(locale);
+			ts.setTranslationSource((IQueryable<IInstallableUnit>) queryable);
+			ts.setLocaleProvider(new LocaleProvider() {
+				public Locale getLocale() {
+					// TODO Auto-generated method stub
+					return locale;
+				}
+			});
 			translationSupports.put(locale, ts);
 		}
 		return ts;
 	}
 
-	public Iterator iterator() {
-		final Iterator[] iteratorCatcher = new Iterator[1];
-		queryable.query(new ContextQuery() {
-			public IQueryResult perform(Iterator iterator) {
+	public Iterator<T> iterator() {
+		@SuppressWarnings("unchecked")
+		final Iterator<T>[] iteratorCatcher = new Iterator[1];
+		queryable.query(new ContextQuery<T>() {
+			public IQueryResult<T> perform(Iterator<T> iterator) {
 				iteratorCatcher[0] = iterator;
 				return null;
 			}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/RepeatableIterator.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/RepeatableIterator.java
index e1419e9a9..743a04c7f 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/RepeatableIterator.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/RepeatableIterator.java
@@ -11,61 +11,62 @@
 package org.eclipse.equinox.internal.p2.ql;
 
 import java.util.*;
-import org.eclipse.equinox.internal.provisional.p2.metadata.query.Collector;
+import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 
-public class RepeatableIterator implements IRepeatableIterator {
-	private final List values;
+public class RepeatableIterator<T> implements IRepeatableIterator<T> {
+	private final List<T> values;
 	private int position = -1;
 
-	public static IRepeatableIterator create(Object unknown) {
+	@SuppressWarnings("unchecked")
+	public static <T> IRepeatableIterator<T> create(Object unknown) {
 		if (unknown.getClass().isArray())
-			return create((Object[]) unknown);
-		if (unknown instanceof Iterator)
-			return create((Iterator) unknown);
-		if (unknown instanceof List)
-			return create((List) unknown);
-		if (unknown instanceof Collection)
-			return create((Collection) unknown);
-		if (unknown instanceof Map)
-			return create(((Map) unknown).entrySet());
-		if (unknown instanceof Collector)
-			return create((Collector) unknown);
+			return create((T[]) unknown);
+		if (unknown instanceof Iterator<?>)
+			return create((Iterator<T>) unknown);
+		if (unknown instanceof List<?>)
+			return create((List<T>) unknown);
+		if (unknown instanceof Collection<?>)
+			return create((Collection<T>) unknown);
+		if (unknown instanceof Map<?, ?>)
+			return create((Set<T>) ((Map<?, ?>) unknown).entrySet());
+		if (unknown instanceof IQueryResult<?>)
+			return create((IQueryResult<T>) unknown);
 		throw new IllegalArgumentException("Cannot convert a " + unknown.getClass().getName() + " into an iterator"); //$NON-NLS-1$ //$NON-NLS-2$
 	}
 
-	public static IRepeatableIterator create(Iterator iterator) {
-		return iterator instanceof IRepeatableIterator ? ((IRepeatableIterator) iterator).getCopy() : new ElementRetainingIterator(iterator);
+	public static <T> IRepeatableIterator<T> create(Iterator<T> iterator) {
+		return iterator instanceof IRepeatableIterator<?> ? ((IRepeatableIterator<T>) iterator).getCopy() : new ElementRetainingIterator<T>(iterator);
 	}
 
-	public static IRepeatableIterator create(List values) {
-		return new RepeatableIterator(values);
+	public static <T> IRepeatableIterator<T> create(List<T> values) {
+		return new RepeatableIterator<T>(values);
 	}
 
-	public static IRepeatableIterator create(Collection values) {
-		return new CollectionIterator(values);
+	public static <T> IRepeatableIterator<T> create(Collection<T> values) {
+		return new CollectionIterator<T>(values);
 	}
 
-	public static IRepeatableIterator create(Collector values) {
-		return new CollectorIterator(values);
+	public static <T> IRepeatableIterator<T> create(IQueryResult<T> values) {
+		return new QueryResultIterator<T>(values);
 	}
 
-	public static IRepeatableIterator create(Object[] values) {
-		return new ArrayIterator(values);
+	public static <T> IRepeatableIterator<T> create(T[] values) {
+		return new ArrayIterator<T>(values);
 	}
 
-	RepeatableIterator(List values) {
+	RepeatableIterator(List<T> values) {
 		this.values = values;
 	}
 
-	public IRepeatableIterator getCopy() {
-		return new RepeatableIterator(values);
+	public IRepeatableIterator<T> getCopy() {
+		return new RepeatableIterator<T>(values);
 	}
 
 	public boolean hasNext() {
 		return position + 1 < values.size();
 	}
 
-	public Object next() {
+	public T next() {
 		if (++position == values.size()) {
 			--position;
 			throw new NoSuchElementException();
@@ -85,15 +86,15 @@ public class RepeatableIterator implements IRepeatableIterator {
 		this.position = position;
 	}
 
-	List getValues() {
+	List<T> getValues() {
 		return values;
 	}
 
-	static class ArrayIterator implements IRepeatableIterator {
-		private final Object[] array;
+	static class ArrayIterator<T> implements IRepeatableIterator<T> {
+		private final T[] array;
 		private int position = -1;
 
-		public ArrayIterator(Object[] array) {
+		public ArrayIterator(T[] array) {
 			this.array = array;
 		}
 
@@ -105,7 +106,7 @@ public class RepeatableIterator implements IRepeatableIterator {
 			return position + 1 < array.length;
 		}
 
-		public Object next() {
+		public T next() {
 			if (++position >= array.length)
 				throw new NoSuchElementException();
 			return array[position];
@@ -115,23 +116,23 @@ public class RepeatableIterator implements IRepeatableIterator {
 			throw new UnsupportedOperationException();
 		}
 
-		public IRepeatableIterator getCopy() {
-			return new ArrayIterator(array);
+		public IRepeatableIterator<T> getCopy() {
+			return new ArrayIterator<T>(array);
 		}
 	}
 
-	static class CollectionIterator implements IRepeatableIterator {
-		private final Collection collection;
+	static class CollectionIterator<T> implements IRepeatableIterator<T> {
+		private final Collection<T> collection;
 
-		private final Iterator iterator;
+		private final Iterator<T> iterator;
 
-		CollectionIterator(Collection collection) {
+		CollectionIterator(Collection<T> collection) {
 			this.collection = collection;
 			this.iterator = collection.iterator();
 		}
 
-		public IRepeatableIterator getCopy() {
-			return new CollectionIterator(collection);
+		public IRepeatableIterator<T> getCopy() {
+			return new CollectionIterator<T>(collection);
 		}
 
 		public Object getIteratorProvider() {
@@ -142,7 +143,7 @@ public class RepeatableIterator implements IRepeatableIterator {
 			return iterator.hasNext();
 		}
 
-		public Object next() {
+		public T next() {
 			return iterator.next();
 		}
 
@@ -151,29 +152,29 @@ public class RepeatableIterator implements IRepeatableIterator {
 		}
 	}
 
-	static class CollectorIterator implements IRepeatableIterator {
-		private final Collector collector;
+	static class QueryResultIterator<T> implements IRepeatableIterator<T> {
+		private final IQueryResult<T> queryResult;
 
-		private final Iterator iterator;
+		private final Iterator<T> iterator;
 
-		CollectorIterator(Collector collector) {
-			this.collector = collector;
-			this.iterator = collector.iterator();
+		QueryResultIterator(IQueryResult<T> queryResult) {
+			this.queryResult = queryResult;
+			this.iterator = queryResult.iterator();
 		}
 
-		public IRepeatableIterator getCopy() {
-			return new CollectorIterator(collector);
+		public IRepeatableIterator<T> getCopy() {
+			return new QueryResultIterator<T>(queryResult);
 		}
 
 		public Object getIteratorProvider() {
-			return collector;
+			return queryResult;
 		}
 
 		public boolean hasNext() {
 			return iterator.hasNext();
 		}
 
-		public Object next() {
+		public T next() {
 			return iterator.next();
 		}
 
@@ -182,12 +183,12 @@ public class RepeatableIterator implements IRepeatableIterator {
 		}
 	}
 
-	static class ElementRetainingIterator extends RepeatableIterator {
+	static class ElementRetainingIterator<T> extends RepeatableIterator<T> {
 
-		private Iterator innerIterator;
+		private Iterator<T> innerIterator;
 
-		ElementRetainingIterator(Iterator iterator) {
-			super(new ArrayList());
+		ElementRetainingIterator(Iterator<T> iterator) {
+			super(new ArrayList<T>());
 			innerIterator = iterator;
 		}
 
@@ -201,16 +202,16 @@ public class RepeatableIterator implements IRepeatableIterator {
 			return super.hasNext();
 		}
 
-		public synchronized Object next() {
+		public synchronized T next() {
 			if (innerIterator != null) {
-				Object val = innerIterator.next();
+				T val = innerIterator.next();
 				getValues().add(val);
 				return val;
 			}
 			return super.next();
 		}
 
-		public synchronized IRepeatableIterator getCopy() {
+		public synchronized IRepeatableIterator<T> getCopy() {
 			// If the current iterator still exists, we must exhaust it first
 			//
 			exhaustInnerIterator();
@@ -224,7 +225,7 @@ public class RepeatableIterator implements IRepeatableIterator {
 
 		private void exhaustInnerIterator() {
 			if (innerIterator != null) {
-				List values = getValues();
+				List<T> values = getValues();
 				int savePos = values.size() - 1;
 				while (innerIterator.hasNext())
 					values.add(innerIterator.next());
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/TranslationSupport.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/TranslationSupport.java
index 2eac137ab..1ece8acfa 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/TranslationSupport.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/TranslationSupport.java
@@ -1,7 +1,11 @@
 package org.eclipse.equinox.internal.p2.ql;
 
+import org.eclipse.equinox.p2.metadata.IInstallableUnit;
 import org.eclipse.equinox.p2.ql.ITranslationSupport;
 
-public class TranslationSupport extends org.eclipse.equinox.p2.common.TranslationSupport implements ITranslationSupport {
-	// The default implementation just uses the common TranslationSupport and adds nothing to the mix.
+public class TranslationSupport extends org.eclipse.equinox.internal.p2.metadata.TranslationSupport implements ITranslationSupport {
+
+	public String getIUProperty(IInstallableUnit iu, String key) {
+		return getIUProperty(iu, key, null);
+	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/All.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/All.java
index 73784486e..a8181dc2c 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/All.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/All.java
@@ -26,7 +26,7 @@ final class All extends CollectionFilter {
 		return TYPE_ALL;
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		Variable variable = lambda.getItemVariable();
 		while (itor.hasNext()) {
 			variable.setValue(context, itor.next());
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/And.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/And.java
index 4ecf87efe..992ad9be5 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/And.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/And.java
@@ -45,10 +45,10 @@ final class And extends NAry {
 		}
 
 		// Not a boolean. Assume that we can use an iterator on all values
-		Set resultSet = asSet(firstValue, false); // Safe since it will not be modified
+		Set<?> resultSet = asSet(firstValue, false); // Safe since it will not be modified
 		for (int idx = 1; idx < operands.length && !resultSet.isEmpty(); ++idx) {
-			Iterator itor = operands[idx].evaluateAsIterator(context);
-			Set retained = new HashSet();
+			Iterator<?> itor = operands[idx].evaluateAsIterator(context);
+			Set<Object> retained = new HashSet<Object>();
 			while (itor.hasNext()) {
 				Object value = itor.next();
 				if (resultSet.contains(value))
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Array.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Array.java
index 0ec90059b..ebba0e5ca 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Array.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Array.java
@@ -19,7 +19,7 @@ import org.eclipse.equinox.p2.ql.IEvaluationContext;
  * An array of expressions
  */
 final class Array extends NAry {
-	final class ArrayIterator implements Iterator {
+	final class ArrayIterator implements Iterator<Object> {
 		private final IEvaluationContext context;
 
 		private int pos = -1;
@@ -64,7 +64,7 @@ final class Array extends NAry {
 		return evaluateAsIterator(context);
 	}
 
-	public Iterator evaluateAsIterator(IEvaluationContext context) {
+	public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
 		return new ArrayIterator(context);
 	}
 
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/At.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/At.java
index f4ae7004c..70b97119f 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/At.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/At.java
@@ -48,18 +48,18 @@ final class At extends Binary {
 		if (lval == null)
 			throw new IllegalArgumentException("Unable to use [] on null"); //$NON-NLS-1$
 
-		if (lval instanceof Map)
-			return ((Map) lval).get(rval);
+		if (lval instanceof Map<?, ?>)
+			return ((Map<?, ?>) lval).get(rval);
 
 		if (rval instanceof Number) {
-			if (lval instanceof List)
-				return ((List) lval).get(((Number) rval).intValue());
+			if (lval instanceof List<?>)
+				return ((List<?>) lval).get(((Number) rval).intValue());
 			if (lval != null && lval.getClass().isArray())
 				return ((Object[]) lval)[((Number) rval).intValue()];
 		}
 
-		if (lval instanceof Dictionary)
-			return ((Dictionary) lval).get(rval);
+		if (lval instanceof Dictionary<?, ?>)
+			return ((Dictionary<?, ?>) lval).get(rval);
 
 		throw new IllegalArgumentException("Unable to use [] on a " + lval.getClass().getName()); //$NON-NLS-1$
 	}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CapabilityIndexFunction.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CapabilityIndexFunction.java
index bd01ae714..99e37e985 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CapabilityIndexFunction.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CapabilityIndexFunction.java
@@ -10,6 +10,7 @@
  *******************************************************************************/
 package org.eclipse.equinox.internal.p2.ql.expression;
 
+import java.util.Iterator;
 import org.eclipse.equinox.internal.p2.ql.CapabilityIndex;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
 import org.eclipse.equinox.p2.ql.IEvaluationContext;
@@ -26,7 +27,7 @@ final class CapabilityIndexFunction extends Function {
 	}
 
 	public Object evaluate(IEvaluationContext context) {
-		return new CapabilityIndex(operands[0].evaluateAsIterator(context));
+		return new CapabilityIndex((Iterator<IInstallableUnit>) operands[0].evaluateAsIterator(context));
 	}
 
 	String getOperator() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Collect.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Collect.java
index 1e858bcaf..fddda5dd5 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Collect.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Collect.java
@@ -17,14 +17,14 @@ import org.eclipse.equinox.p2.ql.IExpression;
 /**
  */
 final class Collect extends CollectionFilter {
-	final class CollectIterator implements Iterator {
+	final class CollectIterator implements Iterator<Object> {
 		private final IEvaluationContext context;
 
 		private final IExpression variable;
 
-		private final Iterator innerIterator;
+		private final Iterator<?> innerIterator;
 
-		public CollectIterator(IEvaluationContext context, Iterator iterator) {
+		public CollectIterator(IEvaluationContext context, Iterator<?> iterator) {
 			this.context = context;
 			this.variable = lambda.getItemVariable();
 			this.innerIterator = iterator;
@@ -48,11 +48,11 @@ final class Collect extends CollectionFilter {
 		super(collection, lambda);
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		return evaluateAsIterator(context, itor);
 	}
 
-	Iterator evaluateAsIterator(IEvaluationContext context, Iterator itor) {
+	Iterator<?> evaluateAsIterator(IEvaluationContext context, Iterator<?> itor) {
 		return new CollectIterator(context, itor);
 	}
 
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CollectionFilter.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CollectionFilter.java
index 325f43f74..b33b28aee 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CollectionFilter.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/CollectionFilter.java
@@ -40,13 +40,13 @@ abstract class CollectionFilter extends Unary {
 	}
 
 	public final Object evaluate(IEvaluationContext context) {
-		Iterator lval = operand.evaluateAsIterator(context);
+		Iterator<?> lval = operand.evaluateAsIterator(context);
 		context = lambda.prolog(context);
 		return evaluate(context, lval);
 	}
 
-	public final Iterator evaluateAsIterator(IEvaluationContext context) {
-		Iterator lval = operand.evaluateAsIterator(context);
+	public final Iterator<?> evaluateAsIterator(IEvaluationContext context) {
+		Iterator<?> lval = operand.evaluateAsIterator(context);
 		context = lambda.prolog(context);
 		return evaluateAsIterator(context, lval);
 	}
@@ -61,9 +61,9 @@ abstract class CollectionFilter extends Unary {
 		return super.countReferenceToEverything() + lambda.countReferenceToEverything();
 	}
 
-	abstract Object evaluate(final IEvaluationContext context, Iterator iterator);
+	abstract Object evaluate(final IEvaluationContext context, Iterator<?> iterator);
 
-	Iterator evaluateAsIterator(IEvaluationContext context, Iterator iterator) {
+	Iterator<?> evaluateAsIterator(IEvaluationContext context, Iterator<?> iterator) {
 		throw new UnsupportedOperationException();
 	}
 
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Constant.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Constant.java
index fdb66aaa3..42c0fe266 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Constant.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Constant.java
@@ -11,6 +11,7 @@
 package org.eclipse.equinox.internal.p2.ql.expression;
 
 import java.util.*;
+import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 import org.eclipse.equinox.p2.ql.IEvaluationContext;
 import org.eclipse.equinox.p2.ql.SimplePattern;
 
@@ -84,7 +85,7 @@ final class Constant extends Expression {
 	}
 
 	boolean isCollection() {
-		return value instanceof Collection || value instanceof Map || value instanceof Iterator || value != null && value.getClass().isArray();
+		return value instanceof Collection<?> || value instanceof Map<?, ?> || value instanceof Iterator<?> || value instanceof IQueryResult<?> || value != null && value.getClass().isArray();
 	}
 
 	String getOperator() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ContextExpression.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ContextExpression.java
index f50b4043d..031eb5017 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ContextExpression.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ContextExpression.java
@@ -19,29 +19,36 @@ import org.eclipse.equinox.p2.ql.*;
  * variable 'everything' and initialized it with the iterator that represents all
  * available items.
  */
-final class ContextExpression extends Unary implements IContextExpression {
+final class ContextExpression<T> extends Unary implements IContextExpression<T> {
 
-	ContextExpression(Expression expression) {
+	private final Class<T> elementClass;
+
+	ContextExpression(Class<T> elementClass, Expression expression) {
 		super(expression);
+		this.elementClass = elementClass;
 	}
 
 	public void toString(StringBuffer bld) {
 		operand.toString(bld);
 	}
 
-	public IEvaluationContext createContext(Class elementClass, Iterator iterator, Object[] params) {
+	public IEvaluationContext createContext(Iterator<T> iterator, Object[] params) {
 		IEvaluationContext context = new SingleVariableContext(new ParameterContext(params), Variable.EVERYTHING);
-		context.setValue(Variable.EVERYTHING, new Everything(elementClass, iterator, operand.needsRepeatedIterations()));
+		context.setValue(Variable.EVERYTHING, new Everything<T>(elementClass, iterator, operand.needsRepeatedIterations()));
 		return context;
 	}
 
-	public IEvaluationContext createContext(Class elementClass, Iterator iterator, Object[] params, ITranslationSupport ts) {
+	public IEvaluationContext createContext(Iterator<T> iterator, Object[] params, ITranslationSupport ts) {
 		IEvaluationContext context = new MultiVariableContext(new ParameterContext(params), new IExpression[] {Variable.EVERYTHING, Variable.TRANSLATIONS});
-		context.setValue(Variable.EVERYTHING, new Everything(elementClass, iterator, operand.needsRepeatedIterations()));
+		context.setValue(Variable.EVERYTHING, new Everything<T>(elementClass, iterator, operand.needsRepeatedIterations()));
 		context.setValue(Variable.TRANSLATIONS, ts);
 		return context;
 	}
 
+	public Class<T> getElementClass() {
+		return elementClass;
+	}
+
 	public int getExpressionType() {
 		return operand.getExpressionType();
 	}
@@ -55,7 +62,7 @@ final class ContextExpression extends Unary implements IContextExpression {
 	}
 
 	Expression pipeFrom(Expression expr) {
-		return new ContextExpression(operand.pipeFrom(expr));
+		return new ContextExpression<T>(elementClass, operand.pipeFrom(expr));
 	}
 
 	boolean isBoolean() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Exists.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Exists.java
index 64a23d7f6..71e967aec 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Exists.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Exists.java
@@ -26,7 +26,7 @@ final class Exists extends CollectionFilter {
 		return TYPE_EXISTS;
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		Variable variable = lambda.getItemVariable();
 		while (itor.hasNext()) {
 			variable.setValue(context, itor.next());
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Expression.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Expression.java
index 46f542964..688ca7f3e 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Expression.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Expression.java
@@ -14,7 +14,7 @@ import java.util.*;
 import org.eclipse.equinox.internal.p2.ql.IRepeatableIterator;
 import org.eclipse.equinox.internal.p2.ql.RepeatableIterator;
 import org.eclipse.equinox.internal.p2.ql.parser.IParserConstants;
-import org.eclipse.equinox.internal.provisional.p2.metadata.query.Collector;
+import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 import org.eclipse.equinox.p2.ql.*;
 
 /**
@@ -24,36 +24,36 @@ abstract class Expression implements IExpression, IParserConstants {
 
 	static final Expression[] emptyArray = new Expression[0];
 
-	static Set asSet(Object val, boolean forcePrivateCopy) {
+	static Set<?> asSet(Object val, boolean forcePrivateCopy) {
 		if (val == null)
 			throw new IllegalArgumentException("Cannot convert null into an set"); //$NON-NLS-1$
 
-		if (val instanceof IRepeatableIterator) {
-			Object provider = ((IRepeatableIterator) val).getIteratorProvider();
+		if (val instanceof IRepeatableIterator<?>) {
+			Object provider = ((IRepeatableIterator<?>) val).getIteratorProvider();
 			if (!forcePrivateCopy) {
-				if (provider instanceof Set)
-					return (Set) provider;
-				if (provider instanceof Collector)
-					return ((Collector) provider).unmodifiableSet();
+				if (provider instanceof Set<?>)
+					return (Set<?>) provider;
+				if (provider instanceof IQueryResult<?>)
+					return ((IQueryResult<?>) provider).unmodifiableSet();
 			}
 
-			if (provider instanceof Collection)
+			if (provider instanceof Collection<?>)
 				val = provider;
 		} else {
 			if (!forcePrivateCopy) {
-				if (val instanceof Set)
-					return (Set) val;
-				if (val instanceof Collector)
-					return ((Collector) val).unmodifiableSet();
+				if (val instanceof Set<?>)
+					return (Set<?>) val;
+				if (val instanceof IQueryResult<?>)
+					return ((IQueryResult<?>) val).unmodifiableSet();
 			}
 		}
 
-		HashSet result;
-		if (val instanceof Collection)
-			result = new HashSet((Collection) val);
+		HashSet<Object> result;
+		if (val instanceof Collection<?>)
+			result = new HashSet<Object>((Collection<?>) val);
 		else {
-			result = new HashSet();
-			Iterator iterator = RepeatableIterator.create(val);
+			result = new HashSet<Object>();
+			Iterator<?> iterator = RepeatableIterator.create(val);
 			while (iterator.hasNext())
 				result.add(iterator.next());
 		}
@@ -77,11 +77,11 @@ abstract class Expression implements IExpression, IParserConstants {
 	 */
 	public abstract Object evaluate(IEvaluationContext context);
 
-	public Iterator evaluateAsIterator(IEvaluationContext context) {
+	public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
 		Object value = evaluate(context);
-		if (!(value instanceof Iterator))
+		if (!(value instanceof Iterator<?>))
 			value = RepeatableIterator.create(value);
-		return (Iterator) value;
+		return (Iterator<?>) value;
 	}
 
 	/**
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ExpressionFactory.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ExpressionFactory.java
index e6dac860d..f603dd6e0 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ExpressionFactory.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/ExpressionFactory.java
@@ -9,11 +9,11 @@ import org.eclipse.equinox.p2.ql.*;
 public class ExpressionFactory implements IExpressionFactory, IParserConstants {
 	public static final IExpressionFactory INSTANCE = new ExpressionFactory();
 
-	private static final Map functionMap;
+	private static final Map<String, Constructor<?>> functionMap;
 
 	static {
-		Class[] args = new Class[] {Expression[].class};
-		Map f = new HashMap();
+		Class<?>[] args = new Class[] {Expression[].class};
+		Map<String, Constructor<?>> f = new HashMap<String, Constructor<?>>();
 		try {
 			f.put(KEYWORD_BOOLEAN, BooleanFunction.class.getConstructor(args));
 			f.put(KEYWORD_FILTER, FilterFunction.class.getConstructor(args));
@@ -71,8 +71,8 @@ public class ExpressionFactory implements IExpressionFactory, IParserConstants {
 		return Constant.create(value);
 	}
 
-	public IContextExpression contextExpression(IExpression expr) {
-		return new ContextExpression((Expression) expr);
+	public <T> IContextExpression<T> contextExpression(Class<T> elementClass, IExpression expr) {
+		return new ContextExpression<T>(elementClass, (Expression) expr);
 	}
 
 	public IExpression dynamicMember(IExpression target, String name) {
@@ -97,7 +97,7 @@ public class ExpressionFactory implements IExpressionFactory, IParserConstants {
 
 	public IExpression function(Object function, IExpression[] args) {
 		try {
-			return (IExpression) ((Constructor) function).newInstance(new Object[] {convertArray(args)});
+			return (IExpression) ((Constructor<?>) function).newInstance(new Object[] {convertArray(args)});
 		} catch (IllegalArgumentException e) {
 			throw e;
 		} catch (InvocationTargetException e) {
@@ -112,7 +112,7 @@ public class ExpressionFactory implements IExpressionFactory, IParserConstants {
 		}
 	}
 
-	public Map getFunctionMap() {
+	public Map<String, ? extends Object> getFunctionMap() {
 		return functionMap;
 	}
 
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/First.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/First.java
index ee20a1466..d587ab0bb 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/First.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/First.java
@@ -26,7 +26,7 @@ final class First extends CollectionFilter {
 		return TYPE_FIRST;
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		Variable variable = lambda.getItemVariable();
 		while (itor.hasNext()) {
 			Object each = itor.next();
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Flatten.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Flatten.java
index 2aaf288ed..bb94afcb7 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Flatten.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Flatten.java
@@ -23,8 +23,8 @@ final class Flatten extends UnaryCollectionFilter {
 		super(collection);
 	}
 
-	public Iterator evaluateAsIterator(IEvaluationContext context) {
-		return new FlattenIterator(operand.evaluateAsIterator(context));
+	public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
+		return new FlattenIterator<Object>(operand.evaluateAsIterator(context));
 	}
 
 	public int getExpressionType() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Latest.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Latest.java
index d4ddc0032..c1557298a 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Latest.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Latest.java
@@ -25,17 +25,17 @@ final class Latest extends UnaryCollectionFilter {
 		super(collection);
 	}
 
-	public Iterator evaluateAsIterator(IEvaluationContext context) {
-		HashMap greatestIUVersion;
+	public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
+		HashMap<String, IVersionedId> greatestIUVersion;
 		if (operand instanceof Select) {
 			// Inline element evaluation here so that we don't build a map that is
 			// larger then it has to be
 			Select select = (Select) operand;
-			Iterator iterator = select.operand.evaluateAsIterator(context);
+			Iterator<?> iterator = select.operand.evaluateAsIterator(context);
 			if (!iterator.hasNext())
 				return Collections.EMPTY_SET.iterator();
 
-			greatestIUVersion = new HashMap();
+			greatestIUVersion = new HashMap<String, IVersionedId>();
 			LambdaExpression lambda = select.lambda;
 			context = lambda.prolog(context);
 			Variable variable = lambda.getItemVariable();
@@ -50,20 +50,20 @@ final class Latest extends UnaryCollectionFilter {
 
 				IVersionedId versionedID = (IVersionedId) next;
 				String id = versionedID.getId();
-				IVersionedId prev = (IVersionedId) greatestIUVersion.put(id, versionedID);
+				IVersionedId prev = greatestIUVersion.put(id, versionedID);
 				if (prev == null)
 					continue;
 				if (prev.getVersion().compareTo(versionedID.getVersion()) > 0)
 					greatestIUVersion.put(id, prev);
 			}
 		} else {
-			Iterator iterator = operand.evaluateAsIterator(context);
+			Iterator<?> iterator = operand.evaluateAsIterator(context);
 			if (iterator == null)
 				return null;
 			if (!iterator.hasNext())
 				return Collections.EMPTY_SET.iterator();
 
-			greatestIUVersion = new HashMap();
+			greatestIUVersion = new HashMap<String, IVersionedId>();
 			while (iterator.hasNext()) {
 				Object next = iterator.next();
 				if (!(next instanceof IVersionedId))
@@ -72,7 +72,7 @@ final class Latest extends UnaryCollectionFilter {
 				IVersionedId versionedID = (IVersionedId) next;
 				String id = versionedID.getId();
 
-				IVersionedId prev = (IVersionedId) greatestIUVersion.put(id, versionedID);
+				IVersionedId prev = greatestIUVersion.put(id, versionedID);
 				if (prev == null)
 					continue;
 
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Limit.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Limit.java
index 5c0ae42a3..926a073b4 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Limit.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Limit.java
@@ -22,11 +22,11 @@ final class Limit extends Binary {
 	/**
 	 * An iterator that stops iterating after a given number of iterations.
 	 */
-	static final class CountingIterator implements Iterator {
-		private final Iterator innerIterator;
+	static final class CountingIterator<T> implements Iterator<T> {
+		private final Iterator<? extends T> innerIterator;
 		private int counter;
 
-		public CountingIterator(Iterator iterator, int count) {
+		public CountingIterator(Iterator<? extends T> iterator, int count) {
 			this.innerIterator = iterator;
 			this.counter = count;
 		}
@@ -35,7 +35,7 @@ final class Limit extends Binary {
 			return counter > 0 && innerIterator.hasNext();
 		}
 
-		public Object next() {
+		public T next() {
 			if (counter > 0) {
 				--counter;
 				return innerIterator.next();
@@ -65,7 +65,7 @@ final class Limit extends Binary {
 			limit = ((Integer) rval).intValue();
 		if (limit <= 0)
 			throw new IllegalArgumentException("limit expression did not evalutate to a positive integer"); //$NON-NLS-1$
-		return new CountingIterator(lhs.evaluateAsIterator(context), limit);
+		return new CountingIterator<Object>(lhs.evaluateAsIterator(context), limit);
 	}
 
 	public int getExpressionType() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Matches.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Matches.java
index b36aa1666..9f9a9e45c 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Matches.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Matches.java
@@ -11,9 +11,9 @@
 package org.eclipse.equinox.internal.p2.ql.expression;
 
 import java.util.*;
-import org.eclipse.equinox.internal.p2.metadata.IRequiredCapability;
 import org.eclipse.equinox.internal.provisional.p2.metadata.*;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
+import org.eclipse.equinox.p2.metadata.IRequirement;
 import org.eclipse.equinox.p2.ql.IEvaluationContext;
 import org.eclipse.equinox.p2.ql.SimplePattern;
 import org.osgi.framework.Filter;
@@ -46,12 +46,12 @@ final class Matches extends Binary {
 		Object lval = lhs.evaluate(context);
 		Object rval = rhs.evaluate(context);
 
-		if (rval instanceof IRequiredCapability) {
-			IRequiredCapability cap = (IRequiredCapability) rval;
+		if (rval instanceof IRequirement) {
+			IRequirement requirement = (IRequirement) rval;
 			if (lval instanceof IInstallableUnit)
-				return Boolean.valueOf(((IInstallableUnit) lval).satisfies(cap));
+				return Boolean.valueOf(((IInstallableUnit) lval).satisfies(requirement));
 			if (lval instanceof IProvidedCapability)
-				return Boolean.valueOf(cap.satisfiedBy((IProvidedCapability) lval));
+				return Boolean.valueOf(((IProvidedCapability) lval).satisfies(requirement));
 
 		} else if (rval instanceof VersionRange) {
 			if (lval instanceof Version)
@@ -67,19 +67,19 @@ final class Matches extends Binary {
 
 		} else if (rval instanceof Filter) {
 			if (lval instanceof IInstallableUnit)
-				return Boolean.valueOf(((Filter) rval).match(new Hashtable(((IInstallableUnit) lval).getProperties())));
-			if (lval instanceof Dictionary)
-				return Boolean.valueOf(((Filter) rval).match((Dictionary) lval));
-			if (lval instanceof Map)
-				return Boolean.valueOf(((Filter) rval).match(new Hashtable((Map) lval)));
+				return Boolean.valueOf(((Filter) rval).match(new Hashtable<String, String>(((IInstallableUnit) lval).getProperties())));
+			if (lval instanceof Dictionary<?, ?>)
+				return Boolean.valueOf(((Filter) rval).match((Dictionary<?, ?>) lval));
+			if (lval instanceof Map<?, ?>)
+				return Boolean.valueOf(((Filter) rval).match(new Hashtable<Object, Object>((Map<?, ?>) lval)));
 
 		} else if (rval instanceof Locale) {
 			if (lval instanceof String)
 				return Boolean.valueOf(matchLocaleVariants((Locale) rval, (String) lval));
 
-		} else if (rval instanceof Class) {
-			Class rclass = (Class) rval;
-			return Boolean.valueOf(lval instanceof Class ? rclass.isAssignableFrom((Class) lval) : rclass.isInstance(lval));
+		} else if (rval instanceof Class<?>) {
+			Class<?> rclass = (Class<?>) rval;
+			return Boolean.valueOf(lval instanceof Class<?> ? rclass.isAssignableFrom((Class<?>) lval) : rclass.isInstance(lval));
 		}
 
 		if (lval == null || rval == null)
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Member.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Member.java
index ff8efbc88..21c99e40c 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Member.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Member.java
@@ -12,6 +12,7 @@ package org.eclipse.equinox.internal.p2.ql.expression;
 
 import java.lang.reflect.*;
 import java.util.Iterator;
+import org.eclipse.equinox.p2.metadata.IRequirement;
 import org.eclipse.equinox.p2.ql.*;
 
 /**
@@ -60,8 +61,9 @@ abstract class Member extends Unary {
 			super(operand, KEYWORD_SATISFIES_ANY, NAry.assertLength(argExpressions, 1, 1, KEYWORD_SATISFIES_ANY));
 		}
 
-		public Iterator evaluateAsIterator(IEvaluationContext context) {
-			return getSelf(context).satisfiesAny(argExpressions[0].evaluateAsIterator(context));
+		@SuppressWarnings("unchecked")
+		public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
+			return getSelf(context).satisfiesAny((Iterator<IRequirement>) argExpressions[0].evaluateAsIterator(context));
 		}
 	}
 
@@ -71,8 +73,9 @@ abstract class Member extends Unary {
 			super(operand, KEYWORD_SATISFIES_ALL, NAry.assertLength(argExpressions, 1, 1, KEYWORD_SATISFIES_ALL));
 		}
 
-		public Iterator evaluateAsIterator(IEvaluationContext context) {
-			return getSelf(context).satisfiesAll(argExpressions[0].evaluateAsIterator(context));
+		@SuppressWarnings("unchecked")
+		public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
+			return getSelf(context).satisfiesAll((Iterator<IRequirement>) argExpressions[0].evaluateAsIterator(context));
 		}
 	}
 
@@ -118,7 +121,7 @@ abstract class Member extends Unary {
 	}
 
 	static final class DynamicMember extends Member {
-		private static final Class[] NO_ARG_TYPES = new Class[0];
+		private static final Class<?>[] NO_ARG_TYPES = new Class[0];
 		private static final String GET_PREFIX = "get"; //$NON-NLS-1$
 		private static final String IS_PREFIX = "is"; //$NON-NLS-1$
 
@@ -129,7 +132,7 @@ abstract class Member extends Unary {
 			this.methodName = name;
 		}
 
-		private Class lastClass;
+		private Class<?> lastClass;
 		private Method method;
 		private String methodName;
 
@@ -145,7 +148,7 @@ abstract class Member extends Unary {
 			if (self == null)
 				throw new IllegalArgumentException("Cannot access member " + name + " in null"); //$NON-NLS-1$//$NON-NLS-2$
 
-			Class c = self.getClass();
+			Class<?> c = self.getClass();
 			if (lastClass == null || !lastClass.isAssignableFrom(c)) {
 				Method m;
 				for (;;) {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Or.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Or.java
index c4fad533a..4892782be 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Or.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Or.java
@@ -47,9 +47,10 @@ final class Or extends NAry {
 		}
 
 		// Not a boolean. Assume that we can use an iterator on all values
-		Set resultSet = asSet(firstValue, true);
+		@SuppressWarnings("unchecked")
+		Set<Object> resultSet = (Set<Object>) asSet(firstValue, true);
 		for (int idx = 1; idx < operands.length; ++idx) {
-			Iterator itor = operands[idx].evaluateAsIterator(context);
+			Iterator<?> itor = operands[idx].evaluateAsIterator(context);
 			while (itor.hasNext())
 				resultSet.add(itor.next());
 		}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Select.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Select.java
index 76ee0cacd..f54ced61d 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Select.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Select.java
@@ -27,12 +27,12 @@ final class Select extends CollectionFilter {
 		return TYPE_SELECT;
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		return evaluateAsIterator(context, itor);
 	}
 
-	Iterator evaluateAsIterator(final IEvaluationContext context, Iterator itor) {
-		return new MatchIteratorFilter(itor) {
+	Iterator<?> evaluateAsIterator(final IEvaluationContext context, Iterator<?> itor) {
+		return new MatchIteratorFilter<Object>(itor) {
 			protected boolean isMatch(Object val) {
 				lambda.getItemVariable().setValue(context, val);
 				return lambda.evaluate(context) == Boolean.TRUE;
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/SetFunction.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/SetFunction.java
index b8c83f10c..3b0fa5248 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/SetFunction.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/SetFunction.java
@@ -20,7 +20,7 @@ final class SetFunction extends Function {
 	}
 
 	public Object evaluate(IEvaluationContext context) {
-		HashSet result = new HashSet();
+		HashSet<Object> result = new HashSet<Object>();
 		for (int idx = 0; idx < operands.length; ++idx)
 			result.add(operands[idx].evaluate(context));
 		return result;
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Traverse.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Traverse.java
index 27fad3ebc..fcb67d6b0 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Traverse.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Traverse.java
@@ -32,12 +32,12 @@ final class Traverse extends CollectionFilter {
 		return TYPE_TRAVERSE;
 	}
 
-	Object evaluate(IEvaluationContext context, Iterator itor) {
+	Object evaluate(IEvaluationContext context, Iterator<?> itor) {
 		return evaluateAsIterator(context, itor);
 	}
 
-	Iterator evaluateAsIterator(IEvaluationContext context, Iterator iterator) {
-		HashSet collector = new HashSet();
+	Iterator<?> evaluateAsIterator(IEvaluationContext context, Iterator<?> iterator) {
+		HashSet<Object> collector = new HashSet<Object>();
 		while (iterator.hasNext())
 			traverse(collector, iterator.next(), context);
 		return collector.iterator();
@@ -47,12 +47,12 @@ final class Traverse extends CollectionFilter {
 		return IParserConstants.KEYWORD_TRAVERSE;
 	}
 
-	void traverse(Set collector, Object parent, IEvaluationContext context) {
+	void traverse(Set<Object> collector, Object parent, IEvaluationContext context) {
 		if (collector.add(parent)) {
 			Variable variable = lambda.getItemVariable();
 			context = new SingleVariableContext(context, variable);
 			variable.setValue(context, parent);
-			Iterator subIterator = lambda.evaluateAsIterator(context);
+			Iterator<?> subIterator = lambda.evaluateAsIterator(context);
 			while (subIterator.hasNext())
 				traverse(collector, subIterator.next(), context);
 		}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Unique.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Unique.java
index 1d592792a..6d55ba1ec 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Unique.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Unique.java
@@ -19,15 +19,15 @@ import org.eclipse.equinox.p2.ql.IEvaluationContext;
  * once throughout the whole query.
  */
 final class Unique extends Binary {
-	static class UniqueIterator extends MatchIteratorFilter {
-		private final Set uniqueSet;
+	static class UniqueIterator<T> extends MatchIteratorFilter<T> {
+		private final Set<T> uniqueSet;
 
-		public UniqueIterator(Iterator iterator, Set uniqueSet) {
+		public UniqueIterator(Iterator<? extends T> iterator, Set<T> uniqueSet) {
 			super(iterator);
 			this.uniqueSet = uniqueSet;
 		}
 
-		protected boolean isMatch(Object val) {
+		protected boolean isMatch(T val) {
 			synchronized (uniqueSet) {
 				return uniqueSet.add(val);
 			}
@@ -40,18 +40,19 @@ final class Unique extends Binary {
 		assertNotBoolean(explicitCache, "cache"); //$NON-NLS-1$
 	}
 
+	@SuppressWarnings("unchecked")
 	public Object evaluate(IEvaluationContext context) {
 		Object explicitCache = rhs.evaluate(context);
-		Set uniqueSet;
+		Set<Object> uniqueSet;
 		if (explicitCache == null)
 			// No cache, we just ensure that the iteration is unique
-			uniqueSet = new HashSet();
+			uniqueSet = new HashSet<Object>();
 		else {
-			if (!(explicitCache instanceof Set))
+			if (!(explicitCache instanceof Set<?>))
 				throw new IllegalArgumentException("Unique cache must be a java.util.Set"); //$NON-NLS-1$
-			uniqueSet = (Set) explicitCache;
+			uniqueSet = (Set<Object>) explicitCache;
 		}
-		return new UniqueIterator(lhs.evaluateAsIterator(context), uniqueSet);
+		return new UniqueIterator<Object>(lhs.evaluateAsIterator(context), uniqueSet);
 	}
 
 	public int getExpressionType() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Variable.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Variable.java
index fcc51ff09..bce472fd0 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Variable.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/Variable.java
@@ -47,12 +47,12 @@ class Variable extends Expression {
 		return context.getValue(this);
 	}
 
-	public Iterator evaluateAsIterator(IEvaluationContext context) {
+	public Iterator<?> evaluateAsIterator(IEvaluationContext context) {
 		Object value = context.getValue(this);
-		if (value instanceof IRepeatableIterator)
-			return ((IRepeatableIterator) value).getCopy();
+		if (value instanceof IRepeatableIterator<?>)
+			return ((IRepeatableIterator<?>) value).getCopy();
 
-		Iterator itor = RepeatableIterator.create(value);
+		Iterator<?> itor = RepeatableIterator.create(value);
 		setValue(context, itor);
 		return itor;
 	}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/WrappedIQuery.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/WrappedIQuery.java
index 282fe452c..fcd3364c1 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/WrappedIQuery.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/expression/WrappedIQuery.java
@@ -23,28 +23,29 @@ final class WrappedIQuery extends Function {
 		assertNotCollection(operands[0], "parameter"); //$NON-NLS-1$
 	}
 
+	@SuppressWarnings("unchecked")
 	public Object evaluate(IEvaluationContext context) {
 		Object query = operands[0].evaluate(context);
 
-		if (query instanceof IMatchQuery) {
+		if (query instanceof IMatchQuery<?>) {
 			Object value = null;
 			if (operands.length > 1)
 				value = operands[1].evaluate(context);
 			else
 				value = Variable.ITEM.evaluate(context);
-			return Boolean.valueOf(((IMatchQuery) query).isMatch(value));
+			return Boolean.valueOf(((IMatchQuery<Object>) query).isMatch(value));
 		}
 
-		if (!(query instanceof IQuery))
+		if (!(query instanceof IQuery<?>))
 			throw new IllegalArgumentException("iquery first argument must be an IQuery instance"); //$NON-NLS-1$
 
-		Iterator iterator = null;
+		Iterator<?> iterator = null;
 		if (operands.length > 1)
 			iterator = operands[1].evaluateAsIterator(context);
 		else
 			iterator = Variable.EVERYTHING.evaluateAsIterator(context);
 
-		return ((IQuery) query).perform(iterator);
+		return ((IQuery<Object>) query).perform((Iterator<Object>) iterator);
 	}
 
 	String getOperator() {
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/parser/ExpressionParser.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/parser/ExpressionParser.java
index 630b71983..bd37c6d2e 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/parser/ExpressionParser.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/parser/ExpressionParser.java
@@ -10,12 +10,10 @@
  *******************************************************************************/
 package org.eclipse.equinox.internal.p2.ql.parser;
 
-import org.eclipse.equinox.p2.ql.IExpression;
-
 import java.util.*;
 import org.eclipse.equinox.p2.ql.*;
 
-public class ExpressionParser extends Stack implements IParserConstants, IExpressionParser {
+public class ExpressionParser extends Stack<IExpression> implements IParserConstants, IExpressionParser {
 	private static final long serialVersionUID = 882034383978853143L;
 
 	private static final int TOKEN_OR = 1;
@@ -66,9 +64,9 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 	private static final int TOKEN_END = 0;
 	private static final int TOKEN_ERROR = -1;
 
-	private static final Map keywords;
+	private static final Map<String, Integer> keywords;
 	static {
-		keywords = new HashMap();
+		keywords = new HashMap<String, Integer>();
 		keywords.put(KEYWORD_ALL, new Integer(TOKEN_ALL));
 		keywords.put(KEYWORD_COLLECT, new Integer(TOKEN_COLLECT));
 		keywords.put(KEYWORD_EXISTS, new Integer(TOKEN_EXISTS));
@@ -116,7 +114,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 		}
 	}
 
-	public synchronized IContextExpression parseQuery(String exprString) {
+	public synchronized <T> IContextExpression<T> parseQuery(Class<T> elementClass, String exprString) {
 		expression = exprString;
 		tokenPos = 0;
 		currentToken = 0;
@@ -128,7 +126,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 			nextToken();
 			IExpression expr = parseCondition();
 			assertToken(TOKEN_END);
-			return factory.contextExpression(expr);
+			return factory.contextExpression(elementClass, expr);
 		} finally {
 			popVariable(); // pop context
 		}
@@ -151,13 +149,13 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 		if (currentToken != TOKEN_OR)
 			return expr;
 
-		ArrayList exprs = new ArrayList();
+		ArrayList<IExpression> exprs = new ArrayList<IExpression>();
 		exprs.add(expr);
 		do {
 			nextToken();
 			exprs.add(parseAnd());
 		} while (currentToken == TOKEN_OR);
-		return factory.or((IExpression[]) exprs.toArray(new IExpression[exprs.size()]));
+		return factory.or(exprs.toArray(new IExpression[exprs.size()]));
 	}
 
 	private IExpression parseAnd() {
@@ -165,13 +163,13 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 		if (currentToken != TOKEN_AND)
 			return expr;
 
-		ArrayList exprs = new ArrayList();
+		ArrayList<IExpression> exprs = new ArrayList<IExpression>();
 		exprs.add(expr);
 		do {
 			nextToken();
 			exprs.add(parseBinary());
 		} while (currentToken == TOKEN_AND);
-		return factory.and((IExpression[]) exprs.toArray(new IExpression[exprs.size()]));
+		return factory.and(exprs.toArray(new IExpression[exprs.size()]));
 	}
 
 	private IExpression parseBinary() {
@@ -456,10 +454,10 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 		int savePos = tokenPos;
 		int saveToken = currentToken;
 		Object saveTokenValue = tokenValue;
-		List ids = null;
+		List<Object> ids = null;
 		while (currentToken == TOKEN_IDENTIFIER) {
 			if (ids == null)
-				ids = new ArrayList();
+				ids = new ArrayList<Object>();
 			ids.add(tokenValue);
 			nextToken();
 			if (currentToken == TOKEN_COMMA) {
@@ -587,7 +585,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 		if (currentToken != TOKEN_COMMA)
 			return new IExpression[] {expr};
 
-		ArrayList operands = new ArrayList();
+		ArrayList<IExpression> operands = new ArrayList<IExpression>();
 		operands.add(expr);
 		do {
 			nextToken();
@@ -596,7 +594,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 				break;
 			operands.add(parseCondition());
 		} while (currentToken == TOKEN_COMMA);
-		return (IExpression[]) operands.toArray(new IExpression[operands.size()]);
+		return operands.toArray(new IExpression[operands.size()]);
 	}
 
 	private void assertToken(int token) {
@@ -607,7 +605,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 	private IExpression getVariableOrRootMember(String id) {
 		int idx = size();
 		while (--idx >= 0) {
-			IExpression v = (IExpression) get(idx);
+			IExpression v = get(idx);
 			if (id.equals(v.toString()))
 				return v;
 		}
@@ -815,7 +813,7 @@ public class ExpressionParser extends Stack implements IParserConstants, IExpres
 					while (tokenPos < top && Character.isJavaIdentifierPart(expression.charAt(tokenPos)))
 						++tokenPos;
 					String word = expression.substring(start, tokenPos);
-					Integer token = (Integer) keywords.get(word);
+					Integer token = keywords.get(word);
 					if (token == null)
 						currentToken = TOKEN_IDENTIFIER;
 					else
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/ICapabilityIndex.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/ICapabilityIndex.java
index 813efe97c..8f6d4a5d1 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/ICapabilityIndex.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/ICapabilityIndex.java
@@ -11,27 +11,27 @@
 package org.eclipse.equinox.p2.ql;
 
 import java.util.Iterator;
-import org.eclipse.equinox.internal.p2.metadata.IRequiredCapability;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
+import org.eclipse.equinox.p2.metadata.IRequirement;
 
 /**
  * An ICapabilityIndex implementation stores instances of {@link IInstallableUnit} so
- * that they are easily retrievable using instances of {@link IRequiredCapability}.
+ * that they are easily retrievable using instances of {@link IRequirement}.
  */
 public interface ICapabilityIndex {
 	/**
 	 * Returns an iterator that will yield all {@link IInstallableUnit} instances that
 	 * satisfies at least one of the <code>requirements</code>.
-	 * @param requirements An iterator over {@link IRequiredCapability} instances.
+	 * @param requirements An iterator over {@link IRequirement} instances.
 	 * @return An iterator over {@link IInstallableUnit} instances. Possibly empty but never <code>null</code>
 	 */
-	Iterator satisfiesAny(Iterator requirements);
+	Iterator<IInstallableUnit> satisfiesAny(Iterator<IRequirement> requirements);
 
 	/**
 	 * Returns an iterator that will yield all {@link IInstallableUnit} instances that
 	 * satisfies all of the <code>requirements</code>.
-	 * @param requirements An iterator over {@link IRequiredCapability} instances.
+	 * @param requirements An iterator over {@link IRequirement} instances.
 	 * @return An iterator over {@link IInstallableUnit} instances. Possibly empty but never <code>null</code>
 	 */
-	Iterator satisfiesAll(Iterator requirements);
+	Iterator<IInstallableUnit> satisfiesAll(Iterator<IRequirement> requirements);
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IContextExpression.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IContextExpression.java
index d573863cc..027e39644 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IContextExpression.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IContextExpression.java
@@ -16,7 +16,13 @@ import java.util.Iterator;
  * This is an expression that will need access to the global variable
  * <code>everything</code>.
  */
-public interface IContextExpression extends IExpression {
+public interface IContextExpression<T> extends IExpression {
+	/**
+	 * Returns the element class
+	 * @return The element class
+	 */
+	Class<T> getElementClass();
+
 	/**
 	 * <p>Creates a new context to be passed to a subsequent evaluation. The context
 	 * will have the variable 'everything' set to an expression that represents
@@ -28,7 +34,7 @@ public interface IContextExpression extends IExpression {
 	 * @param params The parameters to use for the evaluation.
 	 * @return A new evaluation context.
 	 */
-	IEvaluationContext createContext(Class elementClass, Iterator everything, Object[] params);
+	IEvaluationContext createContext(Iterator<T> everything, Object[] params);
 
 	/**
 	 * <p>Creates a new context to be passed to a subsequent evaluation. The context
@@ -42,5 +48,5 @@ public interface IContextExpression extends IExpression {
 	 * @param translations A translation support object to be assigned to the variable 'translations'
 	 * @return A new evaluation context.
 	 */
-	IEvaluationContext createContext(Class elementClass, Iterator everything, Object[] params, ITranslationSupport translations);
+	IEvaluationContext createContext(Iterator<T> everything, Object[] params, ITranslationSupport translations);
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpression.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpression.java
index 040b0ead0..9f959f106 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpression.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpression.java
@@ -72,7 +72,7 @@ public interface IExpression {
 	 * @param context The evaluation context
 	 * @return The result of the evaluation.
 	 */
-	Iterator evaluateAsIterator(IEvaluationContext context);
+	Iterator<?> evaluateAsIterator(IEvaluationContext context);
 
 	/**
 	 * Returns the expression type (see TYPE_xxx constants).
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionFactory.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionFactory.java
index cceafffa2..3ca1ca331 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionFactory.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionFactory.java
@@ -91,7 +91,7 @@ public interface IExpressionFactory {
 	 * @param expr The query
 	 * @return A top level query expression
 	 */
-	IContextExpression contextExpression(IExpression expr);
+	<T> IContextExpression<T> contextExpression(Class<T> elementClass, IExpression expr);
 
 	/**
 	 * Create an expression that tests if <code>lhs</code> is equal to <code>rhs</code>.
@@ -142,7 +142,7 @@ public interface IExpressionFactory {
 	 * method.
 	 * @return A key/function map.
 	 */
-	Map getFunctionMap();
+	Map<String, ? extends Object> getFunctionMap();
 
 	/**
 	 * Create an expression that tests if <code>lhs</code> is greater than <code>rhs</code>.
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionParser.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionParser.java
index 69c507a5b..5dbaf6f57 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionParser.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IExpressionParser.java
@@ -31,5 +31,5 @@ public interface IExpressionParser {
 	 * @return The resulting expression tree.
 	 * @throws QLParseException
 	 */
-	IContextExpression parseQuery(String exprString);
+	<T> IContextExpression<T> parseQuery(Class<T> elementClass, String exprString);
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IQueryContext.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IQueryContext.java
index efc48200d..3268df65f 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IQueryContext.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/IQueryContext.java
@@ -3,8 +3,8 @@ package org.eclipse.equinox.p2.ql;
 import java.util.Iterator;
 import java.util.Locale;
 
-public interface IQueryContext {
+public interface IQueryContext<T> {
 	ITranslationSupport getTranslationSupport(Locale locale);
 
-	Iterator iterator();
+	Iterator<T> iterator();
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QL.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QL.java
index 5b951b683..48bb1aaec 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QL.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QL.java
@@ -41,8 +41,8 @@ public abstract class QL {
 	 * @param queryable The queryable to use for the creation of the context
 	 * @return A new context
 	 */
-	public static IQueryContext newQueryContext(IQueryable queryable) {
-		return new QueryContext(queryable);
+	public static <T> IQueryContext<T> newQueryContext(IQueryable<T> queryable) {
+		return new QueryContext<T>(queryable);
 	}
 
 	/**
@@ -50,7 +50,7 @@ public abstract class QL {
 	 * @param iterator The iterator to use for the creation of the context
 	 * @return A new context
 	 */
-	public static IQueryContext newQueryContext(Iterator iterator) {
-		return new QueryContext(iterator);
+	public static <T> IQueryContext<T> newQueryContext(Iterator<T> iterator) {
+		return new QueryContext<T>(iterator);
 	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLContextQuery.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLContextQuery.java
index 9e3b765d8..d2cd897d1 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLContextQuery.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLContextQuery.java
@@ -11,14 +11,13 @@
 package org.eclipse.equinox.p2.ql;
 
 import java.util.Iterator;
-import org.eclipse.equinox.p2.metadata.IVersionedId;
 import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 
 /**
  * An IQuery 'context query' implementation that is based on the p2 query language.
  */
-public class QLContextQuery extends QLQuery {
-	private final IContextExpression expression;
+public class QLContextQuery<T> extends QLQuery<T> {
+	private final IContextExpression<T> expression;
 
 	/**
 	 * Creates a new query instance with indexed parameters.
@@ -26,8 +25,8 @@ public class QLContextQuery extends QLQuery {
 	 * @param expression The expression that represents the query.
 	 * @param parameters Parameters to use for the query.
 	 */
-	public QLContextQuery(Class elementClass, IContextExpression expression, Object[] parameters) {
-		super(elementClass, parameters);
+	public QLContextQuery(IContextExpression<T> expression, Object... parameters) {
+		super(expression.getElementClass(), parameters);
 		this.expression = expression;
 	}
 
@@ -37,68 +36,24 @@ public class QLContextQuery extends QLQuery {
 	 * @param expression The expression that represents the query.
 	 * @param parameters Parameters to use for the query.
 	 */
-	public QLContextQuery(Class elementClass, String expression, Object[] parameters) {
-		this(elementClass, parser.parseQuery(expression), parameters);
+	public QLContextQuery(Class<T> elementClass, String expression, Object... parameters) {
+		this(parser.parseQuery(elementClass, expression), parameters);
 	}
 
-	/**
-	 * Convenience method that creates a new query instance without parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param elementClass The class used for filtering elements in 'everything' 
-	 * @param expression The expression string that represents the query.
-	 */
-	public QLContextQuery(String expression) {
-		this(IVersionedId.class, expression, noParameters);
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with one parameter.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param elementClass The class used for filtering elements in 'everything' 
-	 * @param expression The expression string that represents the query.
-	 * @param param The first parameter.
-	 */
-	public QLContextQuery(String expression, Object param) {
-		this(IVersionedId.class, expression, new Object[] {param});
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with two parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param elementClass The class used for filtering elements in 'everything' 
-	 * @param expression The expression string that represents the query.
-	 * @param param1 The first parameter.
-	 * @param param2 The second parameter.
-	 */
-	public QLContextQuery(String expression, Object param1, Object param2) {
-		this(IVersionedId.class, expression, new Object[] {param1, param2});
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with three parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param elementClass The class used for filtering elements in 'everything' 
-	 * @param expression The expression string that represents the query.
-	 * @param param1 The first parameter.
-	 * @param param2 The second parameter.
-	 * @param param2 The third parameter.
-	 */
-	public QLContextQuery(String expression, Object param1, Object param2, Object param3) {
-		this(IVersionedId.class, expression, new Object[] {param1, param2, param3});
-	}
-
-	public IQueryResult perform(Iterator iterator) {
-		return new QueryResult(evaluate(iterator));
+	public IQueryResult<T> perform(Iterator<T> iterator) {
+		return new QueryResult<T>(evaluate(iterator));
 	}
 
-	public Iterator evaluate(Iterator iterator) {
+	public Iterator<T> evaluate(Iterator<T> iterator) {
 		IEvaluationContext ctx;
 		if (expression.needsTranslations()) {
-			IQueryContext queryContext = QL.newQueryContext(iterator);
-			ctx = expression.createContext(elementClass, iterator, parameters, queryContext.getTranslationSupport(getLocale()));
+			IQueryContext<T> queryContext = QL.newQueryContext(iterator);
+			ctx = expression.createContext(iterator, parameters, queryContext.getTranslationSupport(getLocale()));
 		} else
-			ctx = expression.createContext(elementClass, iterator, parameters);
-		return expression.evaluateAsIterator(ctx);
+			ctx = expression.createContext(iterator, parameters);
+		@SuppressWarnings("unchecked")
+		Iterator<T> result = (Iterator<T>) expression.evaluateAsIterator(ctx);
+		return result;
 	}
 
 	/**
@@ -106,14 +61,14 @@ public class QLContextQuery extends QLQuery {
 	 * @param queryContext The context for the query.
 	 * @return The result of the query.
 	 */
-	public Object query(IQueryContext queryContext) {
+	public Object query(IQueryContext<T> queryContext) {
 		// Check if we need translation support
 		//
 		IEvaluationContext ctx;
 		if (expression.needsTranslations())
-			ctx = expression.createContext(elementClass, queryContext.iterator(), parameters, queryContext.getTranslationSupport(getLocale()));
+			ctx = expression.createContext(queryContext.iterator(), parameters, queryContext.getTranslationSupport(getLocale()));
 		else
-			ctx = expression.createContext(elementClass, queryContext.iterator(), parameters);
+			ctx = expression.createContext(queryContext.iterator(), parameters);
 		return expression.evaluate(ctx);
 	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLMatchQuery.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLMatchQuery.java
index b43dc2f7f..132db147e 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLMatchQuery.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLMatchQuery.java
@@ -13,13 +13,12 @@ package org.eclipse.equinox.p2.ql;
 import java.util.ArrayList;
 import java.util.Iterator;
 import org.eclipse.equinox.internal.provisional.p2.metadata.query.IMatchQuery;
-import org.eclipse.equinox.p2.metadata.IVersionedId;
 import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 
 /**
  * An IQuery implementation that is based on the p2 query language.
  */
-public class QLMatchQuery extends QLQuery implements IMatchQuery {
+public class QLMatchQuery<T> extends QLQuery<T> implements IMatchQuery<T> {
 	private final IMatchExpression expression;
 	private IEvaluationContext context;
 
@@ -29,7 +28,7 @@ public class QLMatchQuery extends QLQuery implements IMatchQuery {
 	 * @param expression The expression that represents the query.
 	 * @param parameters Parameters to use for the query.
 	 */
-	public QLMatchQuery(Class instanceClass, IMatchExpression expression, Object[] parameters) {
+	public QLMatchQuery(Class<T> instanceClass, IMatchExpression expression, Object... parameters) {
 		super(instanceClass, parameters);
 		this.expression = expression;
 	}
@@ -40,53 +39,11 @@ public class QLMatchQuery extends QLQuery implements IMatchQuery {
 	 * @param expression The expression that represents the query.
 	 * @param parameters Parameters to use for the query.
 	 */
-	public QLMatchQuery(Class instanceClass, String expression, Object[] parameters) {
+	public QLMatchQuery(Class<T> instanceClass, String expression, Object ...parameters) {
 		this(instanceClass, parser.parsePredicate(expression), parameters);
 	}
 
 	/**
-	 * Convenience method that creates a new query instance without parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param expression The expression string that represents the query.
-	 */
-	public QLMatchQuery(String expression) {
-		this(IVersionedId.class, expression, (Object[]) null);
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with one parameter.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param expression The expression string that represents the query.
-	 * @param param The first parameter.
-	 */
-	public QLMatchQuery(String expression, Object param1) {
-		this(IVersionedId.class, expression, new Object[] {param1});
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with two parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param expression The expression string that represents the query.
-	 * @param param1 The first parameter.
-	 * @param param2 The second parameter.
-	 */
-	public QLMatchQuery(String expression, Object param1, Object param2) {
-		this(IVersionedId.class, expression, new Object[] {param1, param2});
-	}
-
-	/**
-	 * Convenience method that creates a new query instance with three parameters.
-	 * The element class defaults to {@link IVersionedId}.
-	 * @param expression The expression string that represents the query.
-	 * @param param1 The first parameter.
-	 * @param param2 The second parameter.
-	 * @param param2 The third parameter.
-	 */
-	public QLMatchQuery(String expression, Object param1, Object param2, Object param3) {
-		this(IVersionedId.class, parser.parsePredicate(expression), new Object[] {param1, param2, param3});
-	}
-
-	/**
 	 * Checks if the <code>candidate</code> object is an instance of the <code>elementClass</code>
 	 * used by this query. If it is, the result calling {@link IMatchExpression#isMatch(IEvaluationContext, Object)}
 	 * on the contained expression is returned.
@@ -94,7 +51,7 @@ public class QLMatchQuery extends QLQuery implements IMatchQuery {
 	 * @return <code>true</code> if <code>candidate</code> is an instance of the element class and the
 	 * expression match test returns true.
 	 */
-	public boolean isMatch(Object candidate) {
+	public boolean isMatch(T candidate) {
 		return elementClass.isInstance(candidate) && expression.isMatch(context, candidate);
 	}
 
@@ -106,22 +63,22 @@ public class QLMatchQuery extends QLQuery implements IMatchQuery {
 		//
 	}
 
-	public IQueryResult perform(Iterator iterator) {
+	public IQueryResult<T> perform(Iterator<T> iterator) {
 		if (expression.needsTranslations()) {
-			IQueryContext queryContext = QL.newQueryContext(iterator);
+			IQueryContext<T> queryContext = QL.newQueryContext(iterator);
 			context = expression.createContext(parameters, queryContext.getTranslationSupport(getLocale()));
 		} else
 			context = expression.createContext(parameters);
 
 		prePerform();
 		try {
-			ArrayList result = new ArrayList();
+			ArrayList<T> result = new ArrayList<T>();
 			while (iterator.hasNext()) {
-				Object candidate = iterator.next();
+				T candidate = iterator.next();
 				if (isMatch(candidate))
 					result.add(candidate);
 			}
-			return new QueryResult(result);
+			return new QueryResult<T>(result);
 		} finally {
 			postPerform();
 		}
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLQuery.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLQuery.java
index 43942ae13..853c4cf41 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLQuery.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QLQuery.java
@@ -12,37 +12,24 @@ package org.eclipse.equinox.p2.ql;
 
 import java.util.Locale;
 import org.eclipse.equinox.internal.provisional.p2.metadata.query.QueryHelpers;
-import org.eclipse.equinox.p2.metadata.IArtifactKey;
 import org.eclipse.equinox.p2.metadata.query.IQuery;
-import org.eclipse.equinox.p2.repository.artifact.IArtifactDescriptor;
-import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
 
 /**
  * An IQuery 'context query' implementation that is based on the p2 query language.
  */
-public abstract class QLQuery implements IQuery {
+public abstract class QLQuery<T> implements IQuery<T> {
 	static final IExpressionParser parser = QL.newParser();
 	static final Object[] noParameters = new Object[0];
 
-	final Class elementClass;
+	final Class<T> elementClass;
 	final Object[] parameters;
 	private Locale locale;
 
-	protected QLQuery(Class elementClass, Object[] parameters) {
+	protected QLQuery(Class<T> elementClass, Object[] parameters) {
 		this.elementClass = elementClass;
 		this.parameters = parameters;
 	}
 
-	public Object getProperty(String key) {
-		if (IArtifactRepository.QUERY_EXCLUDE_KEYS.equals(key))
-			return Boolean.valueOf(!elementClass.isAssignableFrom(IArtifactKey.class));
-
-		if (IArtifactRepository.QUERY_EXCLUDE_DESCRIPTORS.equals(key))
-			return Boolean.valueOf(!elementClass.isAssignableFrom(IArtifactDescriptor.class));
-
-		return QueryHelpers.getProperty(this, key);
-	}
-
 	public Locale getLocale() {
 		return locale == null ? Locale.getDefault() : locale;
 	}
@@ -57,4 +44,8 @@ public abstract class QLQuery implements IQuery {
 	public String getId() {
 		return QueryHelpers.getId(this);
 	}
+
+	public Object getProperty(String property) {
+		return QueryHelpers.getProperty(this, property);
+	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QueryResult.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QueryResult.java
index d634d405f..55b3baf8e 100644
--- a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QueryResult.java
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/p2/ql/QueryResult.java
@@ -9,15 +9,15 @@ import org.eclipse.equinox.internal.provisional.p2.metadata.query.Collector;
 import org.eclipse.equinox.p2.metadata.query.IQuery;
 import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 
-class QueryResult implements IQueryResult {
+class QueryResult<T> implements IQueryResult<T> {
 
-	private final IRepeatableIterator iterator;
+	private final IRepeatableIterator<T> iterator;
 
-	QueryResult(Iterator iterator) {
+	QueryResult(Iterator<T> iterator) {
 		this.iterator = RepeatableIterator.create(iterator);
 	}
 
-	QueryResult(Collection collection) {
+	QueryResult(Collection<T> collection) {
 		this.iterator = RepeatableIterator.create(collection);
 	}
 
@@ -25,53 +25,56 @@ class QueryResult implements IQueryResult {
 		return !iterator.hasNext();
 	}
 
-	public Iterator iterator() {
+	public Iterator<T> iterator() {
 		return iterator.getCopy();
 	}
 
-	public Object[] toArray(Class clazz) {
+	@SuppressWarnings("unchecked")
+	public T[] toArray(Class<? extends T> clazz) {
 		Object provider = iterator.getIteratorProvider();
 		if (provider.getClass().isArray())
-			return (Object[]) provider;
+			return (T[]) provider;
 
-		if (provider instanceof Collector)
-			return ((Collector) provider).toArray(clazz);
+		if (provider instanceof Collector<?>)
+			return ((Collector<T>) provider).toArray(clazz);
 
-		Collection c = (Collection) provider;
-		return c.toArray((Object[]) Array.newInstance(clazz, c.size()));
+		Collection<T> c = (Collection<T>) provider;
+		return c.toArray((T[]) Array.newInstance(clazz, c.size()));
 	}
 
-	public Set toSet() {
+	@SuppressWarnings("unchecked")
+	public Set<T> toSet() {
 		Object provider = iterator.getIteratorProvider();
 		if (provider.getClass().isArray()) {
-			Object[] elems = (Object[]) provider;
+			T[] elems = (T[]) provider;
 			int idx = elems.length;
-			HashSet copy = new HashSet(idx);
+			HashSet<T> copy = new HashSet<T>(idx);
 			while (--idx >= 0)
 				copy.add(elems[idx]);
 			return copy;
 		}
-		if (provider instanceof Collector)
-			return ((Collector) provider).toSet();
-		if (provider instanceof Map)
-			return new HashSet(((Map) provider).entrySet());
-		return new HashSet((Collection) provider);
+		if (provider instanceof Collector<?>)
+			return ((Collector<T>) provider).toSet();
+		if (provider instanceof Map<?, ?>)
+			return new HashSet<T>((Set<T>) ((Map<?, ?>) provider).entrySet());
+		return new HashSet<T>((Collection<T>) provider);
 	}
 
-	public IQueryResult query(IQuery query, IProgressMonitor monitor) {
+	public IQueryResult<T> query(IQuery<T> query, IProgressMonitor monitor) {
 		return query.perform(iterator());
 	}
 
-	public Set unmodifiableSet() {
+	@SuppressWarnings("unchecked")
+	public Set<T> unmodifiableSet() {
 		Object provider = iterator.getIteratorProvider();
-		if (provider instanceof Collector)
-			return ((Collector) provider).unmodifiableSet();
+		if (provider instanceof Collector<?>)
+			return ((Collector<T>) provider).unmodifiableSet();
 
-		if (provider instanceof Set)
-			return Collections.unmodifiableSet((Set) provider);
+		if (provider instanceof Set<?>)
+			return Collections.unmodifiableSet((Set<T>) provider);
 
-		if (provider instanceof Map)
-			return Collections.unmodifiableSet(((Map) provider).entrySet());
+		if (provider instanceof Map<?, ?>)
+			return Collections.unmodifiableSet((Set<T>) ((Map<?, ?>) provider).entrySet());
 
 		return toSet();
 	}