flow4jbsfmanager.java

一个java写的business process management系统

/*
 * Copyright (c) 2003-2004, Alexander Greif
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Flow4J-Eclipse project nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package net.orthanc.flow4j.bsf;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.bsf.BSFManager;

/**
 * @author greifa
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
public class Flow4JBSFManager extends BSFManager {

	private static Flow4JBSFManager instance;
	private List engineDescriptors = new ArrayList();
	private static List builtInEngineDescriptors;

	static {
		builtInEngineDescriptors = new ArrayList();
		
		for (Iterator iter = registeredEngines.entrySet().iterator();
			iter.hasNext();
			) {
			Map.Entry entry = (Map.Entry) iter.next();
			String language = (String) entry.getKey();
			String engineClass = (String) entry.getValue();
			List extensions = new ArrayList();
			for (Iterator iterator = extn2Lang.entrySet().iterator();
				iterator.hasNext();
				) {
				Map.Entry entry2 = (Map.Entry) iterator.next();
				String ext = (String) entry2.getKey();
				if (language.equals((String) entry2.getValue()))
					extensions.add(ext);
			}
			builtInEngineDescriptors.add(new BSFEngineDescriptor(language, engineClass, extensions));
		}

/*		builtInEngineDescriptors.add(
			new BSFEngineDescriptor(
				"jython",
				"org.apache.bsf.engines.jython.JythonEngine",
				new String[] { "py", "python" }));
*/
		builtInEngineDescriptors.add(
			new BSFEngineDescriptor(
				"groovy",
				"org.codehaus.groovy.bsf.GroovyEngine",
				new String[] { "gy", "groovy" }));
	}

	/**
	 * Initialize the known/popular scripting engines
	 *
	 */
	private Flow4JBSFManager() {
		//engineDescriptors.addAll(builtInEngineDescriptors);
		for (Iterator iter = builtInEngineDescriptors.iterator(); iter.hasNext();) {
			BSFEngineDescriptor desc = (BSFEngineDescriptor) iter.next();
			addEngineDescriptor(desc);
		}
	}

	/**
	 * Returns the singleton instance
	 * @return the singleton instance
	 */
	public static Flow4JBSFManager getInstance() {
		if (instance == null)
			instance = new Flow4JBSFManager();
		return instance;
	}

	/**
	 * Returns the engine descriptor for the requested extension
	 * or <code>null</code> if there is no matching engine.
	 * @param extension the script file extension
	 * @return the engine descriptor or <code>null</code> if none 
	 * of them match.
	 */
	public BSFEngineDescriptor getEngineDescriptorByExtension(String extension) {
		for (Iterator iter = engineDescriptors.iterator(); iter.hasNext();) {
			BSFEngineDescriptor desc = (BSFEngineDescriptor) iter.next();
			for (Iterator iterator = desc.getExtensions().iterator();
				iterator.hasNext();
				) {
				String ext = (String) iterator.next();
				if (ext.equalsIgnoreCase(extension.trim()))
					return desc;
			}
		}
		return null;
	}

	/**
	 * Returns the engine descriptor for the requested name
	 * or <code>null</code> if there is no matching engine.
	 * @param extension the script file extension
	 * @return the engine descriptor or <code>null</code> if none 
	 * of them match.
	 */
	public BSFEngineDescriptor getEngineDescriptorByLanguage(String language) {
		for (Iterator iter = engineDescriptors.iterator(); iter.hasNext();) {
			BSFEngineDescriptor desc = (BSFEngineDescriptor) iter.next();
			if (desc.getLanguage().equalsIgnoreCase(language.trim()))
				return desc;
		}
		return null;
	}

	/**
	 * Returns <code>true</code> if the given extension is a script file extension.
	 * @param ext the extension to check
	 * @return <code>true</code> if the given extension is a script file extension
	 * otherwise <code>false</code>.
	 */
	public static boolean isScriptExtension(String ext) {
		for (Iterator iter = getInstance().engineDescriptors.iterator();
			iter.hasNext();
			) {
			BSFEngineDescriptor desc = (BSFEngineDescriptor) iter.next();
			for (Iterator iterator = desc.getExtensions().iterator();
				iterator.hasNext();
				) {
				String extension = (String) iterator.next();
				if (extension.equalsIgnoreCase(ext))
					return true;
			}
		}
		return false;
	}

	/**
	 * @return
	 */
	public BSFEngineDescriptor[] getEngineDescriptors() {
		return (BSFEngineDescriptor[]) engineDescriptors.toArray(
			new BSFEngineDescriptor[engineDescriptors.size()]);
	}

/*	public List getEngineDescriptorsList() {
		return engineDescriptors;
	}
*/
	public void removeEngineDescriptors(BSFEngineDescriptor[] descs) {
		for (int i = 0; i < descs.length; i++) {
			BSFEngineDescriptor descriptor = descs[i];
			engineDescriptors.remove(descriptor);
		}
	}

	public BSFEngineDescriptor newEngineDescriptor(
		String lang,
		String engineClassName,
		String extensions) {
		return new BSFEngineDescriptor(lang, engineClassName, extensions);
	}

	public BSFEngineDescriptor newEngineDescriptor(
		String lang,
		String engineClassName,
		String[] extensionsArray) {
		return new BSFEngineDescriptor(lang, engineClassName, extensionsArray);
	}

	public BSFEngineDescriptor newEngineDescriptor(
		String lang,
		String engineClassName,
		List extensions) {
		return new BSFEngineDescriptor(lang, engineClassName, extensions);
	}

	public void addEngineDescriptors(BSFEngineDescriptor[] descs) {
		for (int i = 0; i < descs.length; i++) {
			BSFEngineDescriptor descriptor = descs[i];
			addEngineDescriptor(descriptor);
		}
	}


	public void addEngineDescriptor(BSFEngineDescriptor desc) {
		BSFEngineDescriptor origDesc = getEngineDescriptorByLanguage(desc.getLanguage());
		if (origDesc != null)
			engineDescriptors.remove(origDesc);
		engineDescriptors.add(desc);
	}



	public boolean isBuiltInEngine(String language) {
		for (Iterator iter = builtInEngineDescriptors.iterator();
			iter.hasNext();
			) {
			BSFEngineDescriptor desc = (BSFEngineDescriptor) iter.next();
			if (language.equalsIgnoreCase(desc.getLanguage()))
				return true;
		}
		return false;
	}

}