### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/internal/core/SetContainerOperation.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/SetContainerOperation.java,v
retrieving revision 1.12
diff -u -r1.12 SetContainerOperation.java
--- model/org/eclipse/jdt/internal/core/SetContainerOperation.java	27 Jun 2008 16:03:51 -0000	1.12
+++ model/org/eclipse/jdt/internal/core/SetContainerOperation.java	18 Dec 2009 06:54:56 -0000
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2008 IBM Corporation and others.
+ * Copyright (c) 2000, 2009 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -10,9 +10,12 @@
  *******************************************************************************/
 package org.eclipse.jdt.internal.core;
 
+import org.eclipse.core.resources.IResourceRuleFactory;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
+import org.eclipse.core.runtime.jobs.ISchedulingRule;
+import org.eclipse.core.runtime.jobs.MultiRule;
 import org.eclipse.jdt.core.IClasspathContainer;
 import org.eclipse.jdt.core.IClasspathEntry;
 import org.eclipse.jdt.core.IJavaElement;
@@ -140,6 +143,23 @@
 		}
 	}
 
+	protected ISchedulingRule getSchedulingRule() {
+		if (this.canChangeResources) {
+			int length = this.affectedProjects.length;
+			IResourceRuleFactory ruleFactory = ResourcesPlugin.getWorkspace().getRuleFactory();
+			ISchedulingRule[] rules = new ISchedulingRule[length + 1];
+
+			for (int index = 0; index < length; index++) {
+				rules[index] = ruleFactory.modifyRule(this.affectedProjects[index].getProject());
+			}
+			// External folders might get changed inside ChangeClasspathOperation.classpathChanged(ClasspathChange)
+			rules[length] = ruleFactory.modifyRule(JavaModelManager.getExternalManager().getExternalFoldersProject());
+
+			return new MultiRule(rules);
+		}
+		return super.getSchedulingRule();
+	}
+	
 	private void verbose_failure(CoreException e) {
 		Util.verbose(
 			"CPContainer SET  - FAILED DUE TO EXCEPTION\n" + //$NON-NLS-1$
Index: model/org/eclipse/jdt/internal/core/UserLibraryManager.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/UserLibraryManager.java,v
retrieving revision 1.18
diff -u -r1.18 UserLibraryManager.java
--- model/org/eclipse/jdt/internal/core/UserLibraryManager.java	6 Jul 2009 06:49:40 -0000	1.18
+++ model/org/eclipse/jdt/internal/core/UserLibraryManager.java	18 Dec 2009 06:54:56 -0000
@@ -152,37 +152,34 @@
 	}
 
 	public void removeUserLibrary(String libName)  {
-		synchronized (this.userLibraries) {
-			IEclipsePreferences instancePreferences = JavaModelManager.getJavaModelManager().getInstancePreferences();
-			String propertyName = CP_USERLIBRARY_PREFERENCES_PREFIX+libName;
-			instancePreferences.remove(propertyName);
-			try {
-				instancePreferences.flush();
-			} catch (BackingStoreException e) {
-				Util.log(e, "Exception while removing user library " + libName); //$NON-NLS-1$
-			}
+		IEclipsePreferences instancePreferences = JavaModelManager.getJavaModelManager().getInstancePreferences();
+		String propertyName = CP_USERLIBRARY_PREFERENCES_PREFIX+libName;
+		instancePreferences.remove(propertyName);
+		try {
+			instancePreferences.flush();
+		} catch (BackingStoreException e) {
+			Util.log(e, "Exception while removing user library " + libName); //$NON-NLS-1$
 		}
-		// this.userLibraries was updated during the PreferenceChangeEvent (see preferenceChange(...))
+		// No need to lock this.userLibraries since SetContainerOperation uses ISchedulingRule now.
 	}
 
-	public void setUserLibrary(String libName, IClasspathEntry[] entries, boolean isSystemLibrary)  {
-		synchronized (this.userLibraries) {
-			IEclipsePreferences instancePreferences = JavaModelManager.getJavaModelManager().getInstancePreferences();
-			String propertyName = CP_USERLIBRARY_PREFERENCES_PREFIX+libName;
-			try {
-				String propertyValue = UserLibrary.serialize(entries, isSystemLibrary);
-				instancePreferences.put(propertyName, propertyValue); // sends out a PreferenceChangeEvent (see preferenceChange(...))
-			} catch (IOException e) {
-				Util.log(e, "Exception while serializing user library " + libName); //$NON-NLS-1$
-				return;
-			}
-			try {
-				instancePreferences.flush();
-			} catch (BackingStoreException e) {
-				Util.log(e, "Exception while saving user library " + libName); //$NON-NLS-1$
-			}
+	public void setUserLibrary(String libName, IClasspathEntry[] entries, boolean isSystemLibrary) {
+		IEclipsePreferences instancePreferences = JavaModelManager.getJavaModelManager().getInstancePreferences();
+		String propertyName = CP_USERLIBRARY_PREFERENCES_PREFIX + libName;
+		try {
+			String propertyValue = UserLibrary.serialize(entries, isSystemLibrary);
+			instancePreferences.put(propertyName, propertyValue); // sends out a PreferenceChangeEvent (see
+																	// preferenceChange(...))
+		} catch (IOException e) {
+			Util.log(e, "Exception while serializing user library " + libName); //$NON-NLS-1$
+			return;
 		}
-		// this.userLibraries was updated during the PreferenceChangeEvent (see preferenceChange(...))
+		try {
+			instancePreferences.flush();
+		} catch (BackingStoreException e) {
+			Util.log(e, "Exception while saving user library " + libName); //$NON-NLS-1$
+		}
+		// No need to lock this.userLibraries since SetContainerOperation uses ISchedulingRule now.
 	}
 
 }