### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/internal/core/JavaModelManager.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/JavaModelManager.java,v
retrieving revision 1.445
diff -u -r1.445 JavaModelManager.java
--- model/org/eclipse/jdt/internal/core/JavaModelManager.java	2 Mar 2010 06:46:01 -0000	1.445
+++ model/org/eclipse/jdt/internal/core/JavaModelManager.java	23 Mar 2010 15:12:07 -0000
@@ -1552,9 +1552,8 @@
 	}
 	
 	public void addNonChainingJar(IPath path) {
-		if (this.nonChainingJars == null)
-			return;
-		this.nonChainingJars.add(path);
+		if (this.nonChainingJars != null)
+			this.nonChainingJars.add(path);
 	}
 
 	/**
@@ -2922,7 +2921,7 @@
 	}
 	
 	private Set loadNonChainingJarsCache() {
-		Set nonChainingJarsCache = Collections.synchronizedSet(new HashSet());
+		Set nonChainingJarsCache = new HashSet();
 		File nonChainingJarsFile = getNonChainingJarsFile();
 		DataInputStream in = null;
 		try {
@@ -2944,7 +2943,7 @@
 				}
 			}
 		}
-		return nonChainingJarsCache;
+		return Collections.synchronizedSet(nonChainingJarsCache);
 	}
 
 	private File getNonChainingJarsFile() {
@@ -2952,9 +2951,12 @@
 	}
 	
 	private Set getNonChainingJarsCache() throws CoreException {
-		if (this.nonChainingJars != null)
+		// Even if there is one entry in the cache, just return it. It may not be 
+		// the complete cache, but avoid going through all the projects to populate the cache.
+		if (this.nonChainingJars != null && this.nonChainingJars.size() > 0) {
 			return this.nonChainingJars;
-		Set result = Collections.synchronizedSet(new HashSet());
+		}
+		Set result = new HashSet();
 		IJavaProject[] projects = getJavaModel().getJavaProjects();
 		for (int i = 0, length = projects.length; i < length; i++) {
 			IJavaProject javaProject = projects[i];
@@ -2969,7 +2971,8 @@
 				}
 			}
 		}
-		return result;
+		this.nonChainingJars = Collections.synchronizedSet(result);
+		return this.nonChainingJars;
 	}
 
 	public void loadVariablesAndContainers() throws CoreException {
@@ -3648,6 +3651,7 @@
 				info.forgetExternalTimestampsAndIndexes();
 			}
 		}
+		resetNonChainingJarsCache();
 	}
 
 	/*
@@ -3690,7 +3694,8 @@
 	}
 	
 	public void resetNonChainingJarsCache() {
-		this.nonChainingJars = null;
+		if (this.nonChainingJars != null) 
+			this.nonChainingJars.clear();
 	}
 
 	/*
#P org.eclipse.jdt.core.tests.model
Index: src/org/eclipse/jdt/core/tests/model/ClasspathTests.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/ClasspathTests.java,v
retrieving revision 1.209
diff -u -r1.209 ClasspathTests.java
--- src/org/eclipse/jdt/core/tests/model/ClasspathTests.java	4 Mar 2010 10:11:58 -0000	1.209
+++ src/org/eclipse/jdt/core/tests/model/ClasspathTests.java	23 Mar 2010 15:12:14 -0000
@@ -6579,5 +6579,67 @@
 		this.deleteProject("P");
 	}
 }
+/**
+ * @bug 302949: FUP of 302949
+ * Test that 
+ * 1) non-chaining jars are cached during classpath resolution and can be retrieved later on
+ * 2) A full save (after resetting the non chaining jars cache) caches the non-chaining jars information
+ * 3) when a project is deleted, the non-chaining jar cache is reset.
+ * 
+ * @see "https://bugs.eclipse.org/bugs/show_bug.cgi?id=305122"
+ * @throws Exception
+ */
+public void testBug305122() throws Exception {
+	try {
+
+		IJavaProject proj = this.createJavaProject("P", new String[] {}, "bin");
+		IClasspathEntry[] classpath = new IClasspathEntry[2];
+
+		addLibrary(proj, "nonchaining.jar", null, new String[0], 
+				new String[] {
+					"META-INF/MANIFEST.MF",
+					"Manifest-Version: 1.0\n",
+				},
+				JavaCore.VERSION_1_4);
+		addLibrary(proj, "chaining.jar", null, new String[0], 
+				new String[] {
+					"META-INF/MANIFEST.MF",
+					"Manifest-Version: 1.0\n" +
+					"Class-Path: chained.jar\n",
+				},
+				JavaCore.VERSION_1_4);
+
+		classpath[0] = JavaCore.newLibraryEntry(new Path("/P/nonchaining.jar"), null, null);
+		classpath[1] = JavaCore.newLibraryEntry(new Path("/P/chaining.jar"), null, null);
+		createFile("/P/chained.jar", "");
+		
+		proj.setRawClasspath(classpath, null);
+		waitForAutoBuild();
+		JavaModelManager manager = JavaModelManager.getJavaModelManager();
+		assertTrue("Non chaining Jar", manager.isNonChainingJar(classpath[0].getPath()));
+		assertFalse("Chaining Jar", manager.isNonChainingJar(classpath[1].getPath()));
+		
+		((JavaProject)proj).resetResolvedClasspath();
+		proj.getResolvedClasspath(true);
+		manager = JavaModelManager.getJavaModelManager();
+		assertTrue("Non chaining Jar", manager.isNonChainingJar(classpath[0].getPath()));
+		assertFalse("Chaining Jar", manager.isNonChainingJar(classpath[1].getPath()));
+
+		((JavaProject)proj).resetResolvedClasspath();
+		IWorkspace workspace = ResourcesPlugin.getWorkspace();
+		workspace.save(true, null);
+		assertTrue("Non chaining Jar", manager.isNonChainingJar(classpath[0].getPath()));
+		assertFalse("Chaining Jar", manager.isNonChainingJar(classpath[1].getPath()));
+		
+		this.deleteProject("P");
+		assertFalse("Chaining Jar", manager.isNonChainingJar(classpath[0].getPath()));
+		assertFalse("Chaining Jar", manager.isNonChainingJar(classpath[1].getPath()));
+		
+	} finally {
+		IProject proj = this.getProject("P");
+		if ( proj != null && proj.exists())
+			this.deleteProject("P");
+	}
+}
 
 }