### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/internal/core/JavaProject.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/JavaProject.java,v
retrieving revision 1.388
diff -u -r1.388 JavaProject.java
--- model/org/eclipse/jdt/internal/core/JavaProject.java	18 Apr 2007 14:30:40 -0000	1.388
+++ model/org/eclipse/jdt/internal/core/JavaProject.java	24 Apr 2007 08:28:34 -0000
@@ -66,6 +66,7 @@
 import org.eclipse.jdt.internal.compiler.util.ObjectVector;
 import org.eclipse.jdt.internal.compiler.util.SuffixConstants;
 import org.eclipse.jdt.internal.core.JavaModelManager.PerProjectInfo;
+import org.eclipse.jdt.internal.core.JavaProjectElementInfo.ProjectCache;
 import org.eclipse.jdt.internal.core.builder.JavaBuilder;
 import org.eclipse.jdt.internal.core.eval.EvaluationContextWrapper;
 import org.eclipse.jdt.internal.core.util.MementoTokenizer;
@@ -1809,6 +1810,10 @@
 	public IProject getProject() {
 		return this.project;
 	}
+	
+	public ProjectCache getProjectCache() throws JavaModelException {
+		return ((JavaProjectElementInfo) getElementInfo()).getProjectCache(this);
+	}
 
 	/**
 	 * @see IJavaProject
Index: model/org/eclipse/jdt/internal/core/JavaProjectElementInfo.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/JavaProjectElementInfo.java,v
retrieving revision 1.46
diff -u -r1.46 JavaProjectElementInfo.java
--- model/org/eclipse/jdt/internal/core/JavaProjectElementInfo.java	23 Apr 2007 10:52:16 -0000	1.46
+++ model/org/eclipse/jdt/internal/core/JavaProjectElementInfo.java	24 Apr 2007 08:28:34 -0000
@@ -37,10 +37,10 @@
 	static final IPackageFragmentRoot[] NO_ROOTS = new IPackageFragmentRoot[0];
 
 	static class ProjectCache {
-		ProjectCache(IPackageFragmentRoot[] allPkgFragmentRootsCache, HashtableOfArrayToObject allPkgFragmentsCache, Map rootToResolvedEntries) {
+		ProjectCache(IPackageFragmentRoot[] allPkgFragmentRootsCache, Map rootToResolvedEntries, Map pkgFragmentsCaches) {
 			this.allPkgFragmentRootsCache = allPkgFragmentRootsCache;
-			this.allPkgFragmentsCache = allPkgFragmentsCache;
 			this.rootToResolvedEntries = rootToResolvedEntries;
+			this.pkgFragmentsCaches = pkgFragmentsCaches;
 		}
 		
 		/*
@@ -50,10 +50,17 @@
 		
 		/*
 		 * A cache of all package fragments in this project.
-		 * (a map from String[] (the package name) to IPackageFragmentRoot[] (the package fragment roots that contain a package fragment with this name)
+		 * (a map from String[] (the package name) to IPackageFragmentRoot[] (the package fragment roots that contain a package fragment with this name))
 		 */
 		public HashtableOfArrayToObject allPkgFragmentsCache;
 		
+		/*
+		 * A cache of package fragments for each package fragment root of this project
+		 * (a map from IPackageFragmentRoot to
+		 *  a map from String[] (the package name) to IPackageFragmentRoot[] (the package fragment roots that contain a package fragment with this name))
+		 */
+		public Map pkgFragmentsCaches;
+		
 		public Map rootToResolvedEntries;		
 	}
 	
@@ -202,47 +209,21 @@
 				reverseMap.clear();
 			}
 			
-			HashMap otherRoots = JavaModelManager.getJavaModelManager().deltaState.otherRoots;
-			HashtableOfArrayToObject fragmentsCache = new HashtableOfArrayToObject();
-			for (int i = 0, length = roots.length; i < length; i++) {
+			HashMap rootInfos = JavaModelManager.getJavaModelManager().deltaState.roots;
+			HashMap pkgFragmentsCaches = new HashMap();
+			int length = roots.length;
+			for (int i = 0; i < length; i++) {
 				IPackageFragmentRoot root = roots[i];
-				IJavaElement[] frags = null;
-				try {
-					if (root.isArchive() 
-							&& !root.isOpen() 
-							&& otherRoots.get(((JarPackageFragmentRoot) root).jarPath) == null/*only if jar belongs to 1 project (https://bugs.eclipse.org/bugs/show_bug.cgi?id=161175)*/) {
-						JarPackageFragmentRootInfo info = new JarPackageFragmentRootInfo();
-						((JarPackageFragmentRoot) root).computeChildren(info, new HashMap());
-						frags = info.children;
-					} else 
-						frags = root.getChildren();
-				} catch (JavaModelException e) {
-					// root doesn't exist: ignore
-					continue;
-				}
-				for (int j = 0, length2 = frags.length; j < length2; j++) {
-					PackageFragment fragment= (PackageFragment) frags[j];
-					String[] pkgName = fragment.names;
-					Object existing = fragmentsCache.get(pkgName);
-					if (existing == null || existing == NO_ROOTS) {
-						fragmentsCache.put(pkgName, root);
-						// ensure super packages (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=119161)
-						// are also in the map
-						addSuperPackageNames(pkgName, fragmentsCache);
-					} else {
-						if (existing instanceof PackageFragmentRoot) {
-							fragmentsCache.put(pkgName, new IPackageFragmentRoot[] {(PackageFragmentRoot) existing, root});
-						} else {
-							IPackageFragmentRoot[] entry= (IPackageFragmentRoot[]) existing;
-							IPackageFragmentRoot[] copy= new IPackageFragmentRoot[entry.length + 1];
-							System.arraycopy(entry, 0, copy, 0, entry.length);
-							copy[entry.length]= root;
-							fragmentsCache.put(pkgName, copy);
-						}
-					}
+				DeltaProcessor.RootInfo rootInfo = (DeltaProcessor.RootInfo) rootInfos.get(root.getPath());
+				if (rootInfo == null || rootInfo.project.equals(project)) {
+					// compute fragment cache
+					HashtableOfArrayToObject fragmentsCache = new HashtableOfArrayToObject();
+					initializePackageNames(root, fragmentsCache);
+					pkgFragmentsCaches.put(root, fragmentsCache);
 				}
 			}
-			cache = new ProjectCache(roots, fragmentsCache, reverseMap);
+			
+			cache = new ProjectCache(roots, reverseMap, pkgFragmentsCaches);
 			this.projectCache = cache;
 		}
 		return cache;
@@ -258,6 +239,42 @@
 		}
 		return this.nonJavaResources;
 	}
+	
+	private void initializePackageNames(IPackageFragmentRoot root, HashtableOfArrayToObject fragmentsCache) {
+		IJavaElement[] frags = null;
+		try {
+			if (!root.isOpen()) {
+				PackageFragmentRootInfo info = root.isArchive() ? new JarPackageFragmentRootInfo() : new PackageFragmentRootInfo();
+				((PackageFragmentRoot) root).computeChildren(info, new HashMap());
+				frags = info.children;
+			} else 
+				frags = root.getChildren();
+		} catch (JavaModelException e) {
+			// root doesn't exist: ignore
+			return;
+		}
+		for (int j = 0, length2 = frags.length; j < length2; j++) {
+			PackageFragment fragment= (PackageFragment) frags[j];
+			String[] pkgName = fragment.names;
+			Object existing = fragmentsCache.get(pkgName);
+			if (existing == null || existing == NO_ROOTS) {
+				fragmentsCache.put(pkgName, root);
+				// ensure super packages (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=119161)
+				// are also in the map
+				addSuperPackageNames(pkgName, fragmentsCache);
+			} else {
+				if (existing instanceof PackageFragmentRoot) {
+					fragmentsCache.put(pkgName, new IPackageFragmentRoot[] {(PackageFragmentRoot) existing, root});
+				} else {
+					IPackageFragmentRoot[] entry= (IPackageFragmentRoot[]) existing;
+					IPackageFragmentRoot[] copy= new IPackageFragmentRoot[entry.length + 1];
+					System.arraycopy(entry, 0, copy, 0, entry.length);
+					copy[entry.length]= root;
+					fragmentsCache.put(pkgName, copy);
+				}
+			}
+		}
+	}
 
 	/*
 	 * Returns whether the given path is a classpath entry or an output location.
@@ -284,6 +301,56 @@
 	 */
 	NameLookup newNameLookup(JavaProject project, ICompilationUnit[] workingCopies) {
 		ProjectCache cache = getProjectCache(project);
+		HashtableOfArrayToObject allPkgFragmentsCache = cache.allPkgFragmentsCache;
+		if (allPkgFragmentsCache == null) {
+			HashMap rootInfos = JavaModelManager.getJavaModelManager().deltaState.roots;
+			IPackageFragmentRoot[] allRoots = cache.allPkgFragmentRootsCache;
+			int length = allRoots.length;
+			allPkgFragmentsCache = new HashtableOfArrayToObject();
+			for (int i = 0; i < length; i++) {
+				IPackageFragmentRoot root = allRoots[i];
+				DeltaProcessor.RootInfo rootInfo = (DeltaProcessor.RootInfo) rootInfos.get(root.getPath());
+				JavaProject rootProject = rootInfo == null ? project : rootInfo.project;
+				HashtableOfArrayToObject fragmentsCache;
+				if (rootProject.equals(project)) {
+					fragmentsCache = (HashtableOfArrayToObject) cache.pkgFragmentsCaches.get(root);
+				} else {
+					// retrieve fragment cache from root project
+					ProjectCache rootProjectCache;
+					try {
+						rootProjectCache = rootProject.getProjectCache();
+					} catch (JavaModelException e) {
+						// project doesn't exit
+						continue;
+					}
+					fragmentsCache = (HashtableOfArrayToObject) rootProjectCache.pkgFragmentsCaches.get(root);
+				}
+				Object[][] keyTable = fragmentsCache.keyTable;
+				for (int j = 0, length2 = keyTable.length; j < length2; j++) {
+					String[] pkgName = (String[]) fragmentsCache.keyTable[j];
+					if (pkgName == null)
+						continue;
+					Object existing = allPkgFragmentsCache.get(pkgName);
+					if (existing == null || existing == NO_ROOTS) {
+						allPkgFragmentsCache.put(pkgName, root);
+						// ensure super packages (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=119161)
+						// are also in the map
+						JavaProjectElementInfo.addSuperPackageNames(pkgName, allPkgFragmentsCache);
+					} else {
+						if (existing instanceof PackageFragmentRoot) {
+							allPkgFragmentsCache.put(pkgName, new IPackageFragmentRoot[] {(PackageFragmentRoot) existing, root});
+						} else {
+							IPackageFragmentRoot[] roots = (IPackageFragmentRoot[]) existing;
+							int rootLength = roots.length;
+							System.arraycopy(roots, 0, roots = new IPackageFragmentRoot[rootLength+1], 0, rootLength);
+							roots[rootLength] = root;
+							allPkgFragmentsCache.put(pkgName, roots);
+						}
+					}
+				}
+			}
+			cache.allPkgFragmentsCache = allPkgFragmentsCache;
+		}
 		return new NameLookup(cache.allPkgFragmentRootsCache, cache.allPkgFragmentsCache, workingCopies, cache.rootToResolvedEntries);
 	}