| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.apache.log4j.chainsaw.plugins; |
| |
| import java.io.File; |
| import java.net.URL; |
| import java.net.URLClassLoader; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.log4j.chainsaw.prefs.SettingsManager; |
| |
| /** |
| * A factory class to create a Classloader that can refenerence jars/classes/resources |
| * within a users plugin directory. |
| * |
| * Currently a work in progress to see if this allows external jars required by |
| * some 3rd party vendors for things like the JMSReceiver. |
| * |
| * @author psmith |
| * |
| * |
| */ |
| public class PluginClassLoaderFactory { |
| private final ClassLoader pluginClassLoader; |
| |
| private static final PluginClassLoaderFactory instance = new PluginClassLoaderFactory(); |
| |
| private PluginClassLoaderFactory() { |
| this.pluginClassLoader= PluginClassLoaderFactory.create(new File(SettingsManager.getInstance().getSettingsDirectory() + File.separator + "plugins")); |
| |
| } |
| |
| public static PluginClassLoaderFactory getInstance() { |
| return instance; |
| } |
| |
| public ClassLoader getClassLoader() { |
| return this.pluginClassLoader; |
| } |
| |
| /** |
| * Creates a Classloader that will be able to access any of the classes found |
| * in any .JAR file contained within the specified directory path, PLUS |
| * the actual Plugin directory itself, so it acts like the WEB-INF/classes directory, |
| * any class file in the directory will be accessible |
| * |
| * @param pluginDirectory |
| * @throws IllegalArgumentException if the pluginDirectory is null, does not exist, or cannot be read |
| * @throws RuntimeException if turning a File into a URL failed, which would be very unexpected |
| * @return |
| */ |
| private static final ClassLoader create(File pluginDirectory) { |
| if(pluginDirectory == null || !pluginDirectory.exists() || !pluginDirectory.canRead()) { |
| return PluginClassLoaderFactory.class.getClassLoader(); |
| } |
| |
| String[] strings = pluginDirectory.list((dir, name) -> name.toUpperCase().endsWith(".JAR")); |
| |
| |
| List list = new ArrayList(); |
| // add the plugin directory as a resource loading path |
| try { |
| list.add(pluginDirectory.toURI().toURL()); |
| } catch (Exception e) { |
| throw new RuntimeException(e.getMessage()); |
| } |
| if (strings !=null) { |
| for (String name : strings) { |
| File file = new File(pluginDirectory, name); |
| try { |
| list.add(file.toURI().toURL()); |
| System.out.println("Added " + file.getAbsolutePath() |
| + " to Plugin class loader list"); |
| } catch (Exception e) { |
| System.err.println("Failed to retrieve the URL for file: " |
| + file.getAbsolutePath()); |
| throw new RuntimeException(e.getMessage()); |
| } |
| } |
| } |
| ClassLoader parent = PluginClassLoaderFactory.class.getClassLoader(); |
| URL[] urls = (URL[]) list.toArray(new URL[list.size()]); |
| return new URLClassLoader(urls, parent); |
| } |
| |
| } |