Associate manifest information with packages

Add a custom classloader to ensure that packages from classes loaded
from nested JARs include manifest information.

spring-launcher/src/main/java/org/springframework/launcher/LaunchedURLClassLoader.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright 2012-2013 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.launcher;
+
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.security.AccessController;
+import java.security.PrivilegedExceptionAction;
+
+import org.springframework.launcher.jar.RandomAccessJarFile;
+
+/**
+ * {@link ClassLoader} used by the {@link Launcher}.
+ * 
+ * @author Phillip Webb
+ */
+public class LaunchedURLClassLoader extends URLClassLoader {
+
+	/**
+	 * Create a new {@link LaunchedURLClassLoader} instance.
+	 * @param urls the URLs from which to load classes and resources
+	 * @param parent the parent class loader for delegation
+	 */
+	public LaunchedURLClassLoader(URL[] urls, ClassLoader parent) {
+		super(urls, parent);
+	}
+
+	@Override
+	protected Class<?> findClass(final String name) throws ClassNotFoundException {
+		int lastDot = name.lastIndexOf('.');
+		if (lastDot != -1) {
+			String packageName = name.substring(0, lastDot);
+			if (getPackage(packageName) == null) {
+				definePackageForFindClass(name, packageName);
+			}
+		}
+		return super.findClass(name);
+	}
+
+	/**
+	 * Define a package before a {@code findClass} call is made. This is necessary to
+	 * ensure that the appropriate manifest for nested JARs associated with the package.
+	 * 
+	 * @param name the class name being found
+	 * @param packageName the pacakge
+	 */
+	private void definePackageForFindClass(final String name, final String packageName) {
+		try {
+			AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() {
+				public Object run() throws ClassNotFoundException {
+					String path = name.replace('.', '/').concat(".class");
+					for (URL url : getURLs()) {
+						try {
+							if (url.getContent() instanceof RandomAccessJarFile) {
+								RandomAccessJarFile jarFile = (RandomAccessJarFile) url
+										.getContent();
+								if (jarFile.getManifest() != null
+										&& jarFile.getJarEntry(path) != null) {
+									definePackage(packageName, jarFile.getManifest(), url);
+								}
+							}
+						}
+						catch (IOException e) {
+						}
+					}
+					return null;
+				}
+			}, AccessController.getContext());
+		}
+		catch (java.security.PrivilegedActionException pae) {
+		}
+	}
+}

spring-launcher/src/main/java/org/springframework/launcher/Launcher.java

@@ -19,7 +19,6 @@ package org.springframework.launcher;
 import java.io.File;
 import java.lang.reflect.Constructor;
 import java.net.URL;
-import java.net.URLClassLoader;
 import java.security.CodeSource;
 import java.security.ProtectionDomain;
 import java.util.ArrayList;
@@ -144,7 +143,7 @@ public abstract class Launcher {
 	 * @throws Exception
 	 */
 	protected ClassLoader createClassLoader(URL[] urls) throws Exception {
-		return new URLClassLoader(urls, getClass().getClassLoader().getParent());
+		return new LaunchedURLClassLoader(urls, getClass().getClassLoader().getParent());
 	}
 
 	/**