Java tutorial
/* * 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.axis2.util; import java.awt.datatransfer.DataFlavor; import java.awt.datatransfer.UnsupportedFlavorException; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.activation.CommandInfo; import javax.activation.CommandMap; import javax.activation.DataHandler; import javax.activation.DataSource; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * This class acts as a wrapper for the javax.activation.DataHandler class. * It is used to store away a (potentially) user-defined content-type value along with * the DataHandler instance. We'll delegate all method calls except for getContentType() * to the real DataHandler instance. */ public class WrappedDataHandler extends DataHandler { private static final Log log = LogFactory.getLog(WrappedDataHandler.class); DataHandler delegate; String contentType; private static FakeDataSource FAKE_DS = new FakeDataSource(); // This class is simply used as a fake DataSource implementation so that the // WrappedDataHandler class can call it's superclass's ctor with a non-null // value that implements DataSource. The FakeDataSource instance will never // be used, however. It's simply a placeholder. private static class FakeDataSource implements DataSource { public String getContentType() { return "application/octet-stream"; } public InputStream getInputStream() throws IOException { throw new UnsupportedOperationException(); } public String getName() { return "FakeDataSource"; } public OutputStream getOutputStream() throws IOException { throw new UnsupportedOperationException(); } } /** * Constructs a new instance of the WrappedDataHandler. * @param _delegate the real DataHandler instance being wrapped * @param _contentType the user-defined contentType associated with the DataHandler instance */ public WrappedDataHandler(DataHandler _delegate, String _contentType) { super(FAKE_DS); delegate = _delegate; contentType = _contentType; if (log.isDebugEnabled()) { log.debug("Created instance of WrappedDatahandler: " + this.toString() + ", contentType=" + contentType + "\nDelegate DataHandler: " + delegate.toString()); } } /* (non-Javadoc) * @see javax.activation.DataHandler#getAllCommands() */ @Override public CommandInfo[] getAllCommands() { return delegate.getAllCommands(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getBean(javax.activation.CommandInfo) */ @Override public Object getBean(CommandInfo paramCommandInfo) { return delegate.getBean(paramCommandInfo); } /* (non-Javadoc) * @see javax.activation.DataHandler#getCommand(java.lang.String) */ @Override public CommandInfo getCommand(String paramString) { return delegate.getCommand(paramString); } /* (non-Javadoc) * @see javax.activation.DataHandler#getContent() */ @Override public Object getContent() throws IOException { return delegate.getContent(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getContentType() */ @Override public String getContentType() { return (contentType != null ? contentType : delegate.getContentType()); } /* (non-Javadoc) * @see javax.activation.DataHandler#getDataSource() */ @Override public DataSource getDataSource() { return delegate.getDataSource(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getInputStream() */ @Override public InputStream getInputStream() throws IOException { return delegate.getInputStream(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getName() */ @Override public String getName() { return delegate.getName(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getOutputStream() */ @Override public OutputStream getOutputStream() throws IOException { return delegate.getOutputStream(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getPreferredCommands() */ @Override public CommandInfo[] getPreferredCommands() { return delegate.getPreferredCommands(); } /* (non-Javadoc) * @see javax.activation.DataHandler#getTransferData(java.awt.datatransfer.DataFlavor) */ @Override public Object getTransferData(DataFlavor paramDataFlavor) throws UnsupportedFlavorException, IOException { return delegate.getTransferData(paramDataFlavor); } /* (non-Javadoc) * @see javax.activation.DataHandler#getTransferDataFlavors() */ @Override public synchronized DataFlavor[] getTransferDataFlavors() { return delegate.getTransferDataFlavors(); } /* (non-Javadoc) * @see javax.activation.DataHandler#isDataFlavorSupported(java.awt.datatransfer.DataFlavor) */ @Override public boolean isDataFlavorSupported(DataFlavor paramDataFlavor) { return delegate.isDataFlavorSupported(paramDataFlavor); } /* (non-Javadoc) * @see javax.activation.DataHandler#setCommandMap(javax.activation.CommandMap) */ @Override public synchronized void setCommandMap(CommandMap paramCommandMap) { delegate.setCommandMap(paramCommandMap); } /* (non-Javadoc) * @see javax.activation.DataHandler#writeTo(java.io.OutputStream) */ @Override public void writeTo(OutputStream paramOutputStream) throws IOException { delegate.writeTo(paramOutputStream); } }