Bug 254955 Collector should handle duplicates

6 files changed, 22 insertions, 19 deletions

diff --git a/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/internal/provisional/p2/query/Collector.java b/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/internal/provisional/p2/query/Collector.java
index 397afc985..ffc892a17 100644
--- a/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/internal/provisional/p2/query/Collector.java
+++ b/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/internal/provisional/p2/query/Collector.java
@@ -23,7 +23,7 @@ import java.util.*;
  * to perform different processing on the objects passed to it.
  */
 public class Collector {
-	private ArrayList collected = null;
+	private Set collected = null;
 
 	/**
 	 * Creates a new collector.
@@ -45,17 +45,21 @@ public class Collector {
 	 * or <code>false</code> to indicate the traversal should stop.
 	 */
 	public boolean accept(Object object) {
-		getList().add(object);
+		getCollection().add(object);
 		return true;
 	}
 
 	/**
-	 * Returns the list that is being used to collect results.
-	 * @return the list being used to collect results.
+	 * Returns the collection that is being used to collect results. Unlike {@toCollection},
+	 * this returns the actual modifiable collection that is being used to store results. The
+	 * return value is only intended to be used within subclasses and should not be exposed
+	 * outside of a collection class.
+	 * 
+	 * @return the collection being used to collect results.
 	 */
-	protected List getList() {
+	protected Collection getCollection() {
 		if (collected == null)
-			collected = new ArrayList();
+			collected = new HashSet();
 		return collected;
 	}
 
@@ -100,7 +104,12 @@ public class Collector {
 		return result;
 	}
 
+	/**
+	 * Returns the collected objects as an immutable collection.
+	 * 
+	 * @return An unmodifiable collection of the collected objects
+	 */
 	public Collection toCollection() {
-		return collected == null ? Collections.EMPTY_LIST : Collections.unmodifiableList(collected);
+		return collected == null ? Collections.EMPTY_SET : Collections.unmodifiableSet(collected);
 	}
 }
diff --git a/bundles/org.eclipse.equinox.p2.director.app/src/org/eclipse/equinox/internal/p2/director/app/LatestIUVersionCollector.java b/bundles/org.eclipse.equinox.p2.director.app/src/org/eclipse/equinox/internal/p2/director/app/LatestIUVersionCollector.java
index 209b66d8e..96281fae6 100644
--- a/bundles/org.eclipse.equinox.p2.director.app/src/org/eclipse/equinox/internal/p2/director/app/LatestIUVersionCollector.java
+++ b/bundles/org.eclipse.equinox.p2.director.app/src/org/eclipse/equinox/internal/p2/director/app/LatestIUVersionCollector.java
@@ -22,7 +22,7 @@ public class LatestIUVersionCollector extends Collector {
 		Object matchElement = uniqueIds.get(iu.getId());
 		if (matchElement == null || iu.getVersion().compareTo(getIU(matchElement).getVersion()) > 0) {
 			if (matchElement != null)
-				getList().remove(matchElement);
+				getCollection().remove(matchElement);
 
 			matchElement = makeDefaultElement(iu);
 			uniqueIds.put(iu.getId(), matchElement);
diff --git a/bundles/org.eclipse.equinox.p2.metadata.generator/src/org/eclipse/equinox/internal/p2/metadata/generator/ProductQuery.java b/bundles/org.eclipse.equinox.p2.metadata.generator/src/org/eclipse/equinox/internal/p2/metadata/generator/ProductQuery.java
index 8486d52b7..5e76dacf8 100644
--- a/bundles/org.eclipse.equinox.p2.metadata.generator/src/org/eclipse/equinox/internal/p2/metadata/generator/ProductQuery.java
+++ b/bundles/org.eclipse.equinox.p2.metadata.generator/src/org/eclipse/equinox/internal/p2/metadata/generator/ProductQuery.java
@@ -41,7 +41,7 @@ public class ProductQuery extends Query {
 				IInstallableUnit existing = (IInstallableUnit) elements.get(iu.getId());
 				if (existing.getVersion().compareTo(iu.getVersion()) >= 0)
 					return true;
-				getList().remove(existing);
+				getCollection().remove(existing);
 			}
 			elements.put(iu.getId(), iu);
 			return super.accept(object);
diff --git a/bundles/org.eclipse.equinox.p2.reconciler.dropins/src/org/eclipse/equinox/internal/p2/reconciler/dropins/ProfileSynchronizer.java b/bundles/org.eclipse.equinox.p2.reconciler.dropins/src/org/eclipse/equinox/internal/p2/reconciler/dropins/ProfileSynchronizer.java
index e560ea048..f6aaef1c8 100644
--- a/bundles/org.eclipse.equinox.p2.reconciler.dropins/src/org/eclipse/equinox/internal/p2/reconciler/dropins/ProfileSynchronizer.java
+++ b/bundles/org.eclipse.equinox.p2.reconciler.dropins/src/org/eclipse/equinox/internal/p2/reconciler/dropins/ProfileSynchronizer.java
@@ -43,12 +43,6 @@ public class ProfileSynchronizer {
 	private static final String NO_TIMESTAMP = "-1"; //$NON-NLS-1$
 	private static final String PROP_FROM_DROPINS = "org.eclipse.equinox.p2.reconciler.dropins"; //$NON-NLS-1$
 
-	public class ListCollector extends Collector {
-		public List getList() {
-			return super.getList();
-		}
-	}
-
 	private static final String CACHE_EXTENSIONS = "org.eclipse.equinox.p2.cache.extensions"; //$NON-NLS-1$
 	private static final String PIPE = "|"; //$NON-NLS-1$
 	final IProfile profile;
diff --git a/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/CategoryElementCollector.java b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/CategoryElementCollector.java
index 826970ced..a66e3d210 100644
--- a/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/CategoryElementCollector.java
+++ b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/CategoryElementCollector.java
@@ -132,15 +132,15 @@ public class CategoryElementCollector extends QueriedElementCollector {
 		ElementQueryDescriptor queryDescriptor = element.getQueryProvider().getQueryDescriptor(element);
 		Collector collector = queryDescriptor.queryable.query(queryDescriptor.query, queryDescriptor.collector, null);
 		if (!collector.isEmpty())
-			getList().add(element);
+			getCollection().add(element);
 	}
 
 	private void removeNestedCategories() {
-		CategoryElement[] categoryIUs = (CategoryElement[]) getList().toArray(new CategoryElement[getList().size()]);
+		CategoryElement[] categoryIUs = (CategoryElement[]) getCollection().toArray(new CategoryElement[getCollection().size()]);
 		// If any other element refers to a category element, remove it from the list
 		for (int i = 0; i < categoryIUs.length; i++) {
 			if (referredIUs.contains(categoryIUs[i].getIU().getId())) {
-				getList().remove(categoryIUs[i]);
+				getCollection().remove(categoryIUs[i]);
 			}
 		}
 	}
diff --git a/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/LatestIUVersionCollector.java b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/LatestIUVersionCollector.java
index 0814fd156..2b80e6c8b 100644
--- a/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/LatestIUVersionCollector.java
+++ b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/p2/ui/query/LatestIUVersionCollector.java
@@ -46,7 +46,7 @@ public class LatestIUVersionCollector extends AvailableIUCollector {
 		Object matchElement = uniqueIds.get(iu.getId());
 		if (matchElement == null || iu.getVersion().compareTo(getIU(matchElement).getVersion()) > 0) {
 			if (matchElement != null)
-				getList().remove(matchElement);
+				getCollection().remove(matchElement);
 			matchElement = makeDefaultElement(iu);
 			uniqueIds.put(iu.getId(), matchElement);
 			return super.accept(matchElement);