| /* |
| * 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 rewrite.org.apache.myfaces.extensions.scripting.core.loader; |
| |
| import rewrite.org.apache.myfaces.extensions.scripting.core.common.util.ClassUtils; |
| import rewrite.org.apache.myfaces.extensions.scripting.core.context.WeavingContext; |
| import rewrite.org.apache.myfaces.extensions.scripting.core.monitor.ClassResource; |
| |
| import java.io.*; |
| import java.util.logging.Level; |
| import java.util.logging.Logger; |
| |
| import static java.util.logging.Level.SEVERE; |
| |
| /** |
| * @author Werner Punz (latest modification by $Author$) |
| * @version $Revision$ $Date$ |
| */ |
| |
| public class ThrowAwayClassloader extends ClassLoader |
| { |
| |
| static final Logger _logger = Logger.getLogger(ThrowAwayClassloader.class.getName()); |
| |
| public ThrowAwayClassloader(ClassLoader classLoader) |
| { |
| super(classLoader); |
| } |
| |
| public ThrowAwayClassloader() |
| { |
| } |
| |
| @Override |
| /** |
| * load called either if the class is not loaded at all |
| * or if the class has been recompiled (check upfront) |
| */ |
| public Class<?> loadClass(String className) throws ClassNotFoundException |
| { |
| ClassResource res = (ClassResource) WeavingContext.getInstance().getResource(className); |
| if (res == null) return super.loadClass(className); |
| if (!res.isTainted() && res.getAClass() != null) return res.getAClass(); |
| File target = resolveClassFile(className); |
| //a load must happen anyway because the target was recompiled |
| int fileLength; |
| byte[] fileContent; |
| FileInputStream iStream = null; |
| //we cannot load while a compile is in progress |
| //we have to wait until it is one |
| try |
| { |
| fileLength = (int) target.length(); |
| fileContent = new byte[fileLength]; |
| iStream = new FileInputStream(target); |
| int result = iStream.read(fileContent); |
| _logger.log(Level.FINER, "read {0} bytes", String.valueOf(result)); |
| } |
| catch (FileNotFoundException e) |
| { |
| throw new ClassNotFoundException(e.toString()); |
| } |
| catch (IOException e) |
| { |
| throw new ClassNotFoundException(e.toString()); |
| } |
| finally |
| { |
| if (iStream != null) |
| { |
| try |
| { |
| iStream.close(); |
| } |
| catch (Exception e) |
| { |
| Logger log = Logger.getLogger(this.getClass().getName()); |
| log.log(SEVERE, "", e); |
| } |
| } |
| } |
| //here we use trick17 we can store as many classes of the same name |
| //as long as we store with a new classloader every time it needs refresh |
| //we need to do it because the classloader can call itself recursively |
| //TODO we might run into issues here with inner classes |
| Class retVal; |
| if (res != null) { |
| retVal = (new ThrowAwayClassloader(getParent())).defineClass(className, fileContent, 0, fileLength); |
| res.setAClass(retVal); |
| res.setTainted(false); |
| } else { |
| retVal = super.defineClass(className, fileContent, 0, fileLength); |
| } |
| return retVal; |
| |
| } |
| |
| @Override |
| public InputStream getResourceAsStream(String name) |
| { |
| File resource = resolveClassFile(name); |
| if (resource.exists()) |
| { |
| try |
| { |
| return new FileInputStream(resource); |
| } |
| catch (FileNotFoundException e) |
| { |
| return super.getResourceAsStream(name); |
| } |
| } |
| return super.getResourceAsStream(name); |
| } |
| |
| private File resolveClassFile(String name) |
| { |
| return ClassUtils.classNameToFile(WeavingContext.getInstance().getConfiguration().getCompileTarget() |
| .getAbsolutePath |
| (), name); |
| |
| } |
| |
| } |