code: /***************************************************************************
   *   Copyright (C) 2007-2015 by Fabrizio Montesi <famontesi@gmail.com>     *
   *                                                                         *
   *   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 jolie.embedding.js;
  
  import java.io.BufferedReader;
  import java.io.FileNotFoundException;
  import java.io.FileReader;
  import java.io.IOException;
  import java.io.Reader;
  import javax.script.Compilable;
  import javax.script.CompiledScript;
  import javax.script.Invocable;
  import javax.script.ScriptEngine;
  import javax.script.ScriptEngineManager;
  import javax.script.ScriptException;
  import jolie.runtime.embedding.EmbeddedServiceLoader;
  import jolie.runtime.embedding.EmbeddedServiceLoaderCreationException;
  import jolie.runtime.embedding.EmbeddedServiceLoadingException;
  import jolie.runtime.expression.Expression;
  
  /**
   *
   * @author Fabrizio Montesi
   */
  public class JavaScriptServiceLoader extends EmbeddedServiceLoader
  {
  	private final ScriptEngine engine;
  
  	public JavaScriptServiceLoader( Expression channelDest, String jsPath )
  		throws EmbeddedServiceLoaderCreationException
  	{
  		super( channelDest );
  		final ScriptEngineManager manager = new ScriptEngineManager();
  		this.engine = manager.getEngineByName( "JavaScript" );
  		if ( engine == null ) {
  			throw new EmbeddedServiceLoaderCreationException( "JavaScript engine not found. Check your system." );
  		}
  
  		final Compilable compilable = (Compilable)engine;
  		try {
  			final Reader reader = new BufferedReader( new FileReader( jsPath ) );
  			try {
  				final CompiledScript compiledScript = compilable.compile( reader );
  				compiledScript.eval();
  			} catch( ScriptException e ) {
  				throw new EmbeddedServiceLoaderCreationException( e );
  			} finally {
  				try {
  					reader.close();
  				} catch( IOException e ) {
  					throw new EmbeddedServiceLoaderCreationException( e );
  				}
  			}
  		} catch( FileNotFoundException e ) {
  			throw new EmbeddedServiceLoaderCreationException( e );
  		}
  	}
  
  	@Override
  	public void load()
  		throws EmbeddedServiceLoadingException
  	{
  		try {
  			final Object json = engine.eval( "JSON" );
  			setChannel( new JavaScriptCommChannel( (Invocable)engine, json ) );
  		} catch( ScriptException e ) {
  			throw new EmbeddedServiceLoadingException( e );
  		}
  	}
  }
  