import java.util.jar.JarFile;

import org.eclipse.core.runtime.IPath;

import org.eclipse.osgi.service.resolver.BundleDescription;

import org.eclipse.pde.core.plugin.IPluginLibrary;

import org.eclipse.pde.internal.core.util.CoreUtility;

	private static final String LIB_CACHE_DIR = ".libcache"; //$NON-NLS-1$

		purgeLibraryCache(fModels);

	/**

	 * Caches the libraries contained in the given external bundle (if not already cached).

	 * The JAR files are stored in the local file system (in the state location

	 * of PDE Core). 

	 * 

	 * @param model Model of an external bundle.

	 * 

	 * @return The cached versions of the JAR files wrapped by this bundle, or

	 * an empty array if the given bundle is not packaged as a JAR or does not contain 

	 * any wrapped libraries.

	 */

	public File[] getCachedLibraryFiles(IPluginModelBase model) {

		File fJarFile = new File(model.getInstallLocation());

		if (!fJarFile.isFile())

			return new File[0];

		BundleDescription desc = model.getBundleDescription();

		IPluginLibrary[] libs = model.getPluginBase().getLibraries();

		File fCacheDir = new File(getLibraryCacheDir(), getBundleLibsCacheDirName(desc));

		List files = new ArrayList();

		for (int i = 0; i < libs.length; i++) {

			String libName = libs[i].getName();

			if (!".".equals(libName)) { //$NON-NLS-1$

				libName = ClasspathUtilCore.expandLibraryName(libName);

				File fDestFile = new File(fCacheDir, libName);

				// assume that an existing file is always valid

				if (!fDestFile.isFile()) {

					try {

						fDestFile.getParentFile().mkdirs();

						extractJar(fJarFile, libName, fDestFile);

						files.add(fDestFile);

					} catch (IOException ie) {

						// do not add file, but log error

						PDECore.logException(ie, "Could not extract JAR file from bundle " + desc.getSymbolicName()); //$NON-NLS-1$

					}

				} else

					files.add(fDestFile);

			}

		}

		return (File[]) files.toArray(new File[0]);

	}

	/**

	 * Delete all the cached JARs of libraries which are currently not contained 

	 * or enabled in the target platform. Will ignore any errors when trying to

	 * delete a directory.

	 * 

	 * @param targetModels The current contents of the target platform.

	 */

	private void purgeLibraryCache(IPluginModelBase[] targetModels) {

		File fCacheDir = getLibraryCacheDir();

		if (!fCacheDir.isDirectory())

			return;

		// build a list with all potential directory names for quick check

		Set bundleKeys = new HashSet();

		for (int i = 0; i < targetModels.length; i++) {

			if (targetModels[i].isEnabled()) {

				BundleDescription desc = targetModels[i].getBundleDescription();

				bundleKeys.add(getBundleLibsCacheDirName(desc));

			}

		}

		File[] fDirs = fCacheDir.listFiles();

		for (int i = 0; i < fDirs.length; i++) {

			if (fDirs[i].isDirectory() && !bundleKeys.contains(fDirs[i].getName()))

				CoreUtility.deleteContent(fDirs[i]);

		}

	}

	/**

	 * @return The directory in the PDE Core's state location where wrapped JARs

	 * from external bundles are stored.

	 */

	private static File getLibraryCacheDir() {

		IPath path = PDECore.getDefault().getStateLocation();

		return new File(path.toFile(), LIB_CACHE_DIR);

	}

	/**

	 * Returns the name of the library cache directory for the given bundle.

	 * 

	 * @param desc Bundle descriptor. 

	 * 

	 * @return <code>[bundle ID]_[bundle version]</code>

	 */

	private static String getBundleLibsCacheDirName(BundleDescription desc) {

		return desc.getSymbolicName() + "_" + desc.getVersion(); //$NON-NLS-1$

	}

	private static void extractJar(File fJarFile, String libName, File fTargetFile) throws IOException {

		JarFile f = new JarFile(fJarFile);

		InputStream in = null;

		try {

			in = f.getInputStream(f.getEntry(libName));

			if (in == null)

				throw new IOException();

			CoreUtility.readFile(in, fTargetFile);

		} finally {

			try {

				f.close();

			} catch (Exception e) {

			}

			try {

				in.close();

			} catch (Exception e) {

			}

		}

	}

			File[] jars = PDECore.getDefault().getModelManager().getExternalModelManager().getCachedLibraryFiles(model);

			for (int i = 0; i < jars.length; i++) {

				Path path = new Path(jars[i].getAbsolutePath());

				addLibraryEntry(path, path, rules, getClasspathAttributes(model), entries);

			}