org.eclipse.cdt.debug.edc.tcf.extension/src/org/eclipse/cdt/debug/edc/tcf/extension/services/AbstractTCFService.java

/*******************************************************************************
 * Copyright (c) 2011 Nokia and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Nokia - Initial API and implementation  June, 2011
 *******************************************************************************/

package org.eclipse.cdt.debug.edc.tcf.extension.services;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import org.eclipse.tm.tcf.protocol.IChannel;
import org.eclipse.tm.tcf.protocol.IChannel.ICommandServer;
import org.eclipse.tm.tcf.protocol.IService;
import org.eclipse.tm.tcf.protocol.IToken;
import org.eclipse.tm.tcf.protocol.JSON;

/**
 * A base TCF service that facilitates service creation in a TCF agent written
 * in Java.
 * 
 * @since 3.0
 */
abstract public class AbstractTCFService implements IService {

	private final IChannel fChannel;

	/**
	 * CommandServer framework.<Br>
	 * A concrete TCF service must implement a concrete command server based on
	 * this. The concrete command server class must be public and should
	 * implement methods in such format:
	 * 
	 * <pre>
	 * public void methodName(IToken token, String cmdName, Object[] args)
	 * </pre>
	 * 
	 * where the "methodName" must be name of a command of the TCF service. See
	 * {Service}Proxy class (e.g. {@link LoggingProxy}) for exact command names.
	 * And the method should not throw more than IOException.
	 */
	abstract protected class AbstractCommandServer implements IChannel.ICommandServer {

		public void command(IToken token, String name, byte[] data) {
			try {
				command(token, name, JSON.parseSequence(data));
			} catch (Throwable x) {
				System.out.println("Exception occured in agent. Closing channel.");
				x.printStackTrace();
				fChannel.terminate(x);
			}
		}

		private void command(IToken token, String name, Object[] args) throws Exception {
			String methodName = name;

			Method handler = null;
			try {
				handler = this.getClass().getMethod(methodName, new Class[] { IToken.class, String.class, Object[].class });
			} catch (SecurityException e) {
				// should not happen
				return;
			} catch (NoSuchMethodException e) {
				// Command not supported yet.
				fChannel.rejectCommand(token);
				return;
			}

			try {
				handler.invoke(this, new Object[] { token, name, args });
			} catch (IllegalArgumentException e) {
				throw e;
			} catch (IllegalAccessException e) {
				throw e;
			} catch (InvocationTargetException e) {
				throw (Exception)e.getCause();
			}
		}
	}

	public AbstractTCFService(IChannel channel) {
		this.fChannel = channel;
		channel.addCommandServer(this, getCommandServer());
	}

	public IChannel getChannel() {
		return fChannel;
	}


	abstract protected ICommandServer getCommandServer();
}