Bug 563537 - Remove unnecessary activator in o.e.c.expressions

The activator in the expressions bundle is purely there for historic
reasons and can be removed safely with a few minor changes. This allows
other bundles that depend on the o.e.c.expressions bundle to start
faster.

Change-Id: Ia83b25a4b4c3c7498c4009c3972fbc299292f00f
Signed-off-by: Alex Blewitt <alex.blewitt@gmail.com>

11 files changed, 20 insertions, 78 deletions

diff --git a/bundles/org.eclipse.core.expressions/META-INF/MANIFEST.MF b/bundles/org.eclipse.core.expressions/META-INF/MANIFEST.MF
index 3f2e5b70b..f2484a604 100644
--- a/bundles/org.eclipse.core.expressions/META-INF/MANIFEST.MF
+++ b/bundles/org.eclipse.core.expressions/META-INF/MANIFEST.MF
@@ -4,7 +4,6 @@ Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.core.expressions; singleton:=true
 Bundle-Version: 3.6.900.qualifier
 Bundle-ClassPath: .
-Bundle-Activator: org.eclipse.core.internal.expressions.ExpressionPlugin
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
 Export-Package: org.eclipse.core.expressions,
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ElementHandler.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ElementHandler.java
index 5975bda05..b0332494f 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ElementHandler.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ElementHandler.java
@@ -17,7 +17,6 @@ import org.w3c.dom.Element;
 
 import org.eclipse.core.internal.expressions.CompositeExpression;
 import org.eclipse.core.internal.expressions.ExpressionMessages;
-import org.eclipse.core.internal.expressions.ExpressionPlugin;
 import org.eclipse.core.internal.expressions.StandardElementHandler;
 
 import org.eclipse.core.runtime.CoreException;
@@ -80,7 +79,7 @@ public abstract class ElementHandler {
 	 * @since 3.3
 	 */
 	public Expression create(ExpressionConverter converter, Element element) throws CoreException {
-		throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(),
+		throw new CoreException(new Status(IStatus.ERROR, ElementHandler.class,
 				IStatus.ERROR,
 				ExpressionMessages.ElementHandler_unsupported_element,
 				null));
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ExpressionConverter.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ExpressionConverter.java
index 7b8cfc5a0..9d299aa9d 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ExpressionConverter.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/expressions/ExpressionConverter.java
@@ -18,7 +18,6 @@ import org.w3c.dom.Node;
 
 import org.eclipse.core.internal.expressions.CompositeExpression;
 import org.eclipse.core.internal.expressions.ExpressionMessages;
-import org.eclipse.core.internal.expressions.ExpressionPlugin;
 import org.eclipse.core.internal.expressions.Messages;
 
 import org.eclipse.core.runtime.Assert;
@@ -126,7 +125,7 @@ public final class ExpressionConverter {
 			for (IConfigurationElement configElement : children) {
 				Expression child= perform(configElement);
 				if (child == null)
-					throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(),
+					throw new CoreException(new Status(IStatus.ERROR, ExpressionConverter.class,
 						IStatus.ERROR,
 						Messages.format(
 							ExpressionMessages.Expression_unknown_element,
@@ -170,7 +169,7 @@ public final class ExpressionConverter {
 			if (child.getNodeType() == Node.ELEMENT_NODE) {
 				Expression exp= perform((Element)child);
 				if (exp == null)
-					throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(),
+					throw new CoreException(new Status(IStatus.ERROR, ExpressionConverter.class,
 						IStatus.ERROR,
 						Messages.format(
 							ExpressionMessages.Expression_unknown_element,
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/AdaptExpression.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/AdaptExpression.java
index b0cd0a8a8..56e1b3d92 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/AdaptExpression.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/AdaptExpression.java
@@ -32,6 +32,8 @@ import org.eclipse.core.runtime.Platform;
 
 public class AdaptExpression extends CompositeExpression {
 
+	private static final String PREFERENCE_NAMESPACE = "org.eclipse.core.expressions"; //$NON-NLS-1$
+
 	private static final String ATT_TYPE= "type"; //$NON-NLS-1$
 
 	/**
@@ -119,7 +121,7 @@ public class AdaptExpression extends CompositeExpression {
 	}
 
 	private boolean forceLoadEnabled() {
-		return Platform.getPreferencesService().getBoolean(ExpressionPlugin.getPluginId(), "forceLoadAdapters", true, //$NON-NLS-1$
+		return Platform.getPreferencesService().getBoolean(PREFERENCE_NAMESPACE, "forceLoadAdapters", true, //$NON-NLS-1$
 				null);
 	}
 
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionPlugin.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionPlugin.java
deleted file mode 100644
index 0966e586e..000000000
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionPlugin.java
+++ /dev/null
@@ -1,58 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2000, 2008 IBM Corporation and others.
- *
- * This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License 2.0
- * which accompanies this distribution, and is available at
- * https://www.eclipse.org/legal/epl-2.0/
- *
- * SPDX-License-Identifier: EPL-2.0
- *
- * Contributors:
- *     IBM Corporation - initial API and implementation
- *******************************************************************************/
-package org.eclipse.core.internal.expressions;
-
-import org.osgi.framework.BundleContext;
-import org.osgi.framework.BundleListener;
-
-import org.eclipse.core.runtime.Plugin;
-
-public class ExpressionPlugin extends Plugin {
-
-	private static ExpressionPlugin fgDefault;
-
-	static BundleListener fgBundleListener;
-
-	private BundleContext fBundleContext;
-
-	public ExpressionPlugin() {
-		fgDefault = this;
-	}
-
-	public static ExpressionPlugin getDefault() {
-		return fgDefault;
-	}
-
-	public static String getPluginId() {
-		return "org.eclipse.core.expressions"; //$NON-NLS-1$
-	}
-
-	@Override
-	public void start(BundleContext context) throws Exception {
-		super.start(context);
-		fBundleContext= context;
-	}
-
-	@Override
-	public void stop(BundleContext context) throws Exception {
-		if (fgBundleListener != null)
-			context.removeBundleListener(fgBundleListener);
-		fgBundleListener= null;
-		super.stop(context);
-	}
-
-	public BundleContext getBundleContext() {
-		return fBundleContext;
-	}
-}
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionStatus.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionStatus.java
index 35b87ab49..a3e6a3a7b 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionStatus.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/ExpressionStatus.java
@@ -93,6 +93,6 @@ public class ExpressionStatus extends Status {
 	 * @param exception a low-level exception, or <code>null</code> if not applicable
 	 */
 	public ExpressionStatus(int errorCode, String message, Throwable exception) {
-		super(IStatus.ERROR, ExpressionPlugin.getPluginId(), errorCode, message, exception);
+		super(IStatus.ERROR, ExpressionStatus.class, errorCode, message, exception);
 	}
 }
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Expressions.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Expressions.java
index 3ba6ab542..83e0d5a36 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Expressions.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Expressions.java
@@ -26,6 +26,7 @@ import java.util.WeakHashMap;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.BundleEvent;
 import org.osgi.framework.BundleListener;
+import org.osgi.framework.FrameworkUtil;
 
 import org.w3c.dom.Element;
 
@@ -137,7 +138,7 @@ public class Expressions {
 		if (fgKnownClasses == null) {
 			fgKnownClasses= new WeakHashMap<>();
 			fgNotFoundClasses = new WeakHashMap<>();
-			BundleContext bundleContext= ExpressionPlugin.getDefault().getBundleContext();
+			BundleContext bundleContext = FrameworkUtil.getBundle(Expressions.class).getBundleContext();
 			BundleListener listener= (BundleEvent event) -> {
 				// Invalidate the caches if any of the bundles is stopped
 				if (event.getType() == BundleEvent.STOPPED) {
@@ -147,7 +148,6 @@ public class Expressions {
 					}
 				}
 			};
-			ExpressionPlugin.fgBundleListener = listener;
 			bundleContext.addBundleListener(listener);
 		}
 	}
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Property.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Property.java
index ec8d40c67..d14b44756 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Property.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/Property.java
@@ -65,7 +65,7 @@ public class Property {
 			return fTester.test(receiver, fName, args, expectedValue);
 		} catch (Exception e) {
 			String message = "Error evaluating " + this; //$NON-NLS-1$
-			throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(), message, e));
+			throw new CoreException(new Status(IStatus.ERROR, Property.class, message, e));
 		}
 	}
 
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/PropertyTesterDescriptor.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/PropertyTesterDescriptor.java
index 8be417719..f4888aef3 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/PropertyTesterDescriptor.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/PropertyTesterDescriptor.java
@@ -38,7 +38,7 @@ public class PropertyTesterDescriptor implements IPropertyTester {
 		fConfigElement= element;
 		fNamespace= fConfigElement.getAttribute(NAMESPACE);
 		if (fNamespace == null) {
-			throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(),
+			throw new CoreException(new Status(IStatus.ERROR, PropertyTesterDescriptor.class,
 				IStatus.ERROR,
 				ExpressionMessages.PropertyTesterDescriptor_no_namespace,
 				null));
@@ -46,7 +46,7 @@ public class PropertyTesterDescriptor implements IPropertyTester {
 		StringBuilder buffer= new StringBuilder(","); //$NON-NLS-1$
 		String properties= element.getAttribute(PROPERTIES);
 		if (properties == null) {
-			throw new CoreException(new Status(IStatus.ERROR, ExpressionPlugin.getPluginId(),
+			throw new CoreException(new Status(IStatus.ERROR, PropertyTesterDescriptor.class,
 				IStatus.ERROR,
 				ExpressionMessages.PropertyTesterDescritpri_no_properties,
 				null));
diff --git a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/TypeExtensionManager.java b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/TypeExtensionManager.java
index f5bfa6bd9..51ba182d7 100644
--- a/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/TypeExtensionManager.java
+++ b/bundles/org.eclipse.core.expressions/src/org/eclipse/core/internal/expressions/TypeExtensionManager.java
@@ -31,6 +31,7 @@ import org.eclipse.core.runtime.Platform;
 
 public class TypeExtensionManager implements IRegistryChangeListener {
 
+	private static final String EXTENSION_NAMESPACE = "org.eclipse.core.expressions"; //$NON-NLS-1$
 	private String fExtensionPoint;
 
 	/**
@@ -167,8 +168,7 @@ public class TypeExtensionManager implements IRegistryChangeListener {
 			fConfigurationElementMap= new HashMap<>();
 			IExtensionRegistry registry= Platform.getExtensionRegistry();
 			IConfigurationElement[] ces= registry.getConfigurationElementsFor(
-				ExpressionPlugin.getPluginId(),
-				fExtensionPoint);
+					EXTENSION_NAMESPACE, fExtensionPoint);
 			for (IConfigurationElement config : ces) {
 				String typeAttr= config.getAttribute(TYPE);
 				List<IConfigurationElement> typeConfigs= fConfigurationElementMap.get(typeAttr);
@@ -190,7 +190,7 @@ public class TypeExtensionManager implements IRegistryChangeListener {
 				try {
 					result[i]= new PropertyTesterDescriptor(config);
 				} catch (CoreException e) {
-					ExpressionPlugin.getDefault().getLog().log(e.getStatus());
+					Platform.getLog(TypeExtensionManager.class).log(e.getStatus());
 					result[i]= NULL_PROPERTY_TESTER;
 				}
 			}
@@ -201,7 +201,7 @@ public class TypeExtensionManager implements IRegistryChangeListener {
 
 	@Override
 	public void registryChanged(IRegistryChangeEvent event) {
-		IExtensionDelta[] deltas= event.getExtensionDeltas(ExpressionPlugin.getPluginId(), fExtensionPoint);
+		IExtensionDelta[] deltas = event.getExtensionDeltas(EXTENSION_NAMESPACE, fExtensionPoint);
 		if (deltas.length > 0) {
 			initializeCaches();
 		}
diff --git a/tests/org.eclipse.core.expressions.tests/src/org/eclipse/core/internal/expressions/tests/ExpressionTestsPluginUnloading.java b/tests/org.eclipse.core.expressions.tests/src/org/eclipse/core/internal/expressions/tests/ExpressionTestsPluginUnloading.java
index 124413276..054fe982f 100644
--- a/tests/org.eclipse.core.expressions.tests/src/org/eclipse/core/internal/expressions/tests/ExpressionTestsPluginUnloading.java
+++ b/tests/org.eclipse.core.expressions.tests/src/org/eclipse/core/internal/expressions/tests/ExpressionTestsPluginUnloading.java
@@ -26,8 +26,8 @@ import org.junit.rules.TestName;
 import org.junit.runners.MethodSorters;
 import org.osgi.framework.Bundle;
 import org.osgi.framework.BundleContext;
+import org.osgi.framework.FrameworkUtil;
 
-import org.eclipse.core.internal.expressions.ExpressionPlugin;
 import org.eclipse.core.internal.expressions.Expressions;
 
 
@@ -47,7 +47,8 @@ public class ExpressionTestsPluginUnloading {
 	public void test01PluginStopping() throws Exception {
 		Bundle bundle= getBundle("com.ibm.icu");
 
-		assertEquals(Bundle.STARTING, bundle.getState());
+		int state = bundle.getState();
+		assertTrue(state == Bundle.STARTING || state == Bundle.ACTIVE);
 
 		doTestInstanceofICUDecimalFormat(bundle);
 		assertEquals(Bundle.ACTIVE, bundle.getState());
@@ -103,7 +104,7 @@ public class ExpressionTestsPluginUnloading {
 	}
 
 	private static Bundle getBundle(String bundleName) {
-		BundleContext bundleContext= ExpressionPlugin.getDefault().getBundleContext();
+		BundleContext bundleContext = FrameworkUtil.getBundle(ExpressionTestsPluginUnloading.class).getBundleContext();
 		Bundle[] bundles= bundleContext.getBundles();
 		for (Bundle bundle : bundles) {
 			if (bundleName.equals(bundle.getSymbolicName())) {