code: /***************************************************************************
   *   Copyright (C) 2008 by Fabrizio Montesi                                *
   *                                                                         *
   *   This program is free software; you can redistribute it and/or modify  *
   *   it under the terms of the GNU Library General Public License as       *
   *   published by the Free Software Foundation; either version 2 of the    *
   *   License, or (at your option) any later version.                       *
   *                                                                         *
   *   This program is distributed in the hope that it will be useful,       *
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
   *   GNU General Public License for more details.                          *
   *                                                                         *
   *   You should have received a copy of the GNU Library General Public     *
   *   License along with this program; if not, write to the                 *
   *   Free Software Foundation, Inc.,                                       *
   *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
   *                                                                         *
   *   For details about the authors of this software, see the AUTHORS file. *
   ***************************************************************************/
  
  package joliex.metaservice.impl;
  
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.util.concurrent.ExecutionException;
  import java.util.concurrent.Future;
  import jolie.CommandLineException;
  import jolie.Interpreter;
  import jolie.net.CommChannel;
  import joliex.metaservice.MetaService;
  import joliex.metaservice.MetaServiceChannel;
  
  /**
   * This class executes a MetaService service in the local Java Virtual Machine.
   * @author Fabrizio Montesi
   */
  public class EmbeddedMetaService extends MetaService
  {	
  	private final Interpreter interpreter;
  	private final MetaServiceChannel channel;
  	private static final String fs = jolie.lang.Constants.fileSeparator;
  	private static final String ps = jolie.lang.Constants.pathSeparator;
  
  	private static final String JOLIE_HOME_ENV = "JOLIE_HOME";
  
  	private static final String defaultFilepath = fs + "include" + fs + "services" + fs + "metaservice" + fs + "metaservice.ol";
  	
  	private static String[] buildInterpreterArguments( String jh, String metaServiceFilepath )
  	{
  		// jh stays for jolie_home, i.e. the JOLIE installation directory
  		return new String[] {
  			// Location
  			"-C", "MetaServiceLocation=\"local\"",
  			// Libraries
  			"-l", jh + fs + "lib" + ps + jh + fs + "javaServices" + fs + "*" + ps + jh + fs + "extensions" + fs + "*",
  			// Includes
  			"-i", jh + fs + "include",
  			// MetaService source file
  			metaServiceFilepath
  		};
  	}
  	
  	/**
  	 * Creates an embedded MetaService instance, 
  	 * executing a JOLIE interpreter in the local JVM.
  	 */
  	public EmbeddedMetaService()
  		throws IOException, ExecutionException
  	{
  		this( System.getenv( JOLIE_HOME_ENV ) );
  	}
  
  	/**
  	 * Creates an embedded MetaService instance, 
  	 * executing a JOLIE interpreter in the local JVM.
  	 * @param jolieHome the path pointing to the local JOLIE installation directory.
  	 */
  	public EmbeddedMetaService( String jolieHome )
  		throws IOException, ExecutionException
  	{
  		this( jolieHome, jolieHome + defaultFilepath );
  	}
  	
  	private void startInterpreter()
  		throws ExecutionException
  	{
  		Future< Exception > f = interpreter.start();
  		try {
  			Exception e = f.get();
  			if ( e != null ) {
  				throw new ExecutionException( e );
  			}
  		} catch( InterruptedException e ) {
  			throw new ExecutionException( e );
  		}
  	}
  	
  	/**
  	 * Creates an embedded MetaService instance, 
  	 * executing a JOLIE interpreter in the local JVM.
  	 * @param jolieHome the path pointing to the local JOLIE installation directory.
  	 * @param metaserviceFilepath the path pointing to the metaservice source file to load.
  	 */
  	public EmbeddedMetaService( String jolieHome, String metaserviceFilepath )
  		throws IOException, ExecutionException
  	{
  		try {
  			interpreter =
  				new Interpreter( buildInterpreterArguments( jolieHome, metaserviceFilepath ), this.getClass().getClassLoader(), null );
  			startInterpreter();
  			channel = new MetaServiceChannel( this, "/" );
  		} catch( CommandLineException e ) {
  			throw new IOException( e );
  		} catch( FileNotFoundException e ) {
  			throw new IOException( e );
  		}
  	}
  	
  	protected CommChannel createCommChannel()
  	{
  		return interpreter.commCore().getLocalCommChannel();
  	}
  	
  	public MetaServiceChannel getChannel()
  	{
  		return channel;
  	}
  }
  