### 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 1.429
diff -u -r1.429 JavaProject.java
--- model/org/eclipse/jdt/internal/core/JavaProject.java	2 Mar 2010 06:46:00 -0000	1.429
+++ model/org/eclipse/jdt/internal/core/JavaProject.java	3 Mar 2010 08:16:18 -0000
@@ -2159,44 +2159,17 @@
 			return false;
 
 		// then look at resolved entries
-		for (int i = 0; i < length; i++) {
-			IClasspathEntry rawEntry = rawClasspath[i];
-			switch (rawEntry.getEntryKind()) {
-				case IClasspathEntry.CPE_CONTAINER:
-					IClasspathContainer container;
-					try {
-						container = JavaCore.getClasspathContainer(rawEntry.getPath(), this);
-					} catch (JavaModelException e) {
-						break;
-					}
-					if (container == null)
-						break;
-					IClasspathEntry[] containerEntries = container.getClasspathEntries();
-					if (containerEntries == null)
-						break;
-					// container was bound
-					for (int j = 0, containerLength = containerEntries.length; j < containerLength; j++){
-						IClasspathEntry resolvedEntry = containerEntries[j];
-						if (resolvedEntry == null) {
-							if (JavaModelManager.CP_RESOLVE_VERBOSE || JavaModelManager.CP_RESOLVE_VERBOSE_FAILURE) {
-								JavaModelManager.getJavaModelManager().verbose_missbehaving_container(this, rawEntry.getPath(), containerEntries);
-							}
-							return false;
-						}
-						if (isOnClasspathEntry(elementPath, isFolderPath, isPackageFragmentRoot, resolvedEntry))
-							return true;
-					}
-					break;
-				case IClasspathEntry.CPE_VARIABLE:
-					IClasspathEntry resolvedEntry = JavaCore.getResolvedClasspathEntry(rawEntry);
-					if (resolvedEntry == null)
-						break;
-					if (isOnClasspathEntry(elementPath, isFolderPath, isPackageFragmentRoot, resolvedEntry))
-						return true;
-					break;
-			}
+		IClasspathEntry[] resolvedClasspath = null;
+		try {
+			resolvedClasspath = getResolvedClasspath();
+		} catch(JavaModelException e){
+			return false; // Perhaps, not a Java project
 		}
 
+		for (int index = 0; index< resolvedClasspath.length; index++) {
+			if (isOnClasspathEntry(elementPath, isFolderPath, isPackageFragmentRoot, resolvedClasspath[index]))
+				return true;
+		}
 		return false;
 	}
 
#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 1.208
diff -u -r1.208 ClasspathTests.java
--- src/org/eclipse/jdt/core/tests/model/ClasspathTests.java	2 Mar 2010 06:45:42 -0000	1.208
+++ src/org/eclipse/jdt/core/tests/model/ClasspathTests.java	3 Mar 2010 08:16:30 -0000
@@ -89,7 +89,7 @@
 static {
 	// Names of tests to run: can be "testBugXXXX" or "BugXXXX")
 //	TESTS_PREFIX = "testClasspathDuplicateExtraAttribute";
-//	TESTS_NAMES = new String[] {"testClasspathValidation42"};
+//	TESTS_NAMES = new String[] {"testBug304081"};
 //	TESTS_NUMBERS = new int[] { 23, 28, 38 };
 //	TESTS_RANGE = new int[] { 21, 38 };
 }
@@ -4881,7 +4881,7 @@
  */
 public void testNoResourceChange06() throws CoreException {
 	ILogListener listener = new ILogListener(){
-		private StringBuffer buffer = new StringBuffer();
+		private final StringBuffer buffer = new StringBuffer();
 		public void logging(IStatus status, String plugin) {
 			this.buffer.append(status);
 			this.buffer.append('\n');
@@ -6427,5 +6427,156 @@
 		deleteProject("P");
 	}
 }
+/**
+ * @bug 304081:IJavaProject#isOnClasspath(IJavaElement) returns false for type from referenced JAR
+ * When the JAR, which a variable classpath entry resolves to, references other JAR via
+ * MANIFEST, test that {@link IJavaProject#isOnClasspath(IJavaElement)} returns true
+ * for the referenced classpath entries. 
+ * 
+ * @see "https://bugs.eclipse.org/bugs/show_bug.cgi?id=304081"
+ * @throws Exception
+ */
+public void testBug304081() throws Exception {
+	File libDir = null;
+	try {
+
+		IJavaProject proj = this.createJavaProject("P", new String[] {}, "bin");
+		IPath libPath = proj.getResource().getLocation();
+		JavaCore.setClasspathVariable("MyVar", libPath, null);
+		libDir = new File(libPath.toPortableString());
+		IClasspathEntry[] classpath = new IClasspathEntry[1];
+		File libJar = new File(libDir, "variable.jar");
+		libJar.createNewFile();
+		
+		addLibrary(proj, "variable.jar", null, new String[0], 
+				new String[] {
+				"META-INF/MANIFEST.MF",
+				"Manifest-Version: 1.0\n" +
+				"Class-Path: lib1.jar\n",
+			},
+			JavaCore.VERSION_1_4); 
+
+		createFile("/P/lib1.jar", "");
+		
+		classpath[0] = JavaCore.newVariableEntry(new Path(
+				"/MyVar/variable.jar"), null, null);
+		
+		proj.setRawClasspath(classpath, null);
+		waitForAutoBuild();
+		IProject project = getWorkspaceRoot().getProject("P");
+		IResource resource = project.getFile("variable.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		IJavaElement element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+
+		resource = project.getFile("lib1.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+	} finally {
+		this.deleteProject("P");
+		JavaCore.removeClasspathVariable("MyVar", null);
+	}
+}
+/**
+ * Additional tests for 304081
+ * When the JAR, which is in the raw classpath, references other JAR via
+ * MANIFEST, test that {@link IJavaProject#isOnClasspath(IJavaElement)} returns true
+ * for the referenced classpath entries. 
+ * 
+ * @see "https://bugs.eclipse.org/bugs/show_bug.cgi?id=304081"
+ * @throws Exception
+ */
+public void testBug304081a() throws Exception {
+	try {
+
+		IJavaProject proj = this.createJavaProject("P", new String[] {}, "bin");
+		IClasspathEntry[] classpath = new IClasspathEntry[1];
+
+		addLibrary(proj, "library.jar", null, new String[0], 
+				new String[] {
+					"META-INF/MANIFEST.MF",
+					"Manifest-Version: 1.0\n" +
+					"Class-Path: lib1.jar\n",
+				},
+				JavaCore.VERSION_1_4);
+		createFile("/P/lib1.jar", "");	
+		classpath[0] = JavaCore.newLibraryEntry(new Path("/P/library.jar"), null, null);
+		
+		proj.setRawClasspath(classpath, null);
+		waitForAutoBuild();
+		IProject project = getWorkspaceRoot().getProject("P");
+		IResource resource = project.getFile("library.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		IJavaElement element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+
+		resource = project.getFile("lib1.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+	} finally {
+		this.deleteProject("P");
+	}
+}
+/**
+ * Additional tests for 304081
+ * When the JAR, which is part of a classpath container, references other JAR via
+ * MANIFEST, test that {@link IJavaProject#isOnClasspath(IJavaElement)} returns true
+ * for the referenced classpath entries. 
+ * 
+ * @see "https://bugs.eclipse.org/bugs/show_bug.cgi?id=304081"
+ * @throws Exception
+ */
+public void testBug304081b() throws Exception {
+	File libDir = null;
+	try {
+
+		IJavaProject proj = this.createJavaProject("P", new String[] {}, "bin");
+		IClasspathEntry[] classpath = new IClasspathEntry[1];
+		File libJar = new File(libDir, "container.jar");
+		
+		addLibrary(proj, "container.jar", null, new String[0], 
+				new String[] {
+					"META-INF/MANIFEST.MF",
+					"Manifest-Version: 1.0\n" +
+					"Class-Path: lib1.jar\n",
+				},
+				JavaCore.VERSION_1_4);
+		createFile("/P/lib1.jar", "");
+		
+		ClasspathContainerInitializer initializer= JavaCore.getClasspathContainerInitializer(JavaCore.USER_LIBRARY_CONTAINER_ID);
+		String libraryName = "TestUserLibrary";
+		IPath containerPath = new Path(JavaCore.USER_LIBRARY_CONTAINER_ID);
+		UserLibraryClasspathContainer containerSuggestion = new UserLibraryClasspathContainer(libraryName);
+		initializer.requestClasspathContainerUpdate(containerPath.append(libraryName), null, containerSuggestion);
+
+		IEclipsePreferences preferences = new InstanceScope().getNode(JavaCore.PLUGIN_ID);
+		String propertyName = JavaModelManager.CP_USERLIBRARY_PREFERENCES_PREFIX+"TestUserLibrary";
+		StringBuffer propertyValue = new StringBuffer("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\r\n<userlibrary systemlibrary=\"false\" version=\"1\">\r\n<archive");
+		propertyValue.append(" path=\"" + libJar.getAbsolutePath());
+		propertyValue.append("\"/>\r\n</userlibrary>\r\n");
+		preferences.put(propertyName, propertyValue.toString());
+		preferences.flush();	
+		
+		classpath[0] = JavaCore.newContainerEntry(containerSuggestion.getPath());
+		
+		proj.setRawClasspath(classpath, null);
+		waitForAutoBuild();
+		IProject project = getWorkspaceRoot().getProject("P");
+		IResource resource = project.getFile("container.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		IJavaElement element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+
+		resource = project.getFile("lib1.jar");
+		assertTrue(proj.isOnClasspath(resource));
+		element = proj.getPackageFragmentRoot(resource);
+		assertTrue(proj.isOnClasspath(element));
+		
+	} finally {
+		this.deleteProject("P");
+	}
+}
 
 }