hal/src/zutil/plugin/PluginData.java

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 Ziver Koc
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package zutil.plugin;

import zutil.log.LogUtil;
import zutil.parser.DataNode;

import java.net.MalformedURLException;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * This class contains information about a plugin
 * and implementation instances of the plugin interfaces
 *  
 * @author Ziver
 */
public class PluginData {
	private static Logger log = LogUtil.getLogger();

	private double pluginVersion;
	private String pluginName;
	private HashMap<Class<?>, List<Class<?>>>  classMap;
	private HashMap<Class, Object> objectMap;

	
	protected PluginData(DataNode data) throws ClassNotFoundException, MalformedURLException {
		classMap = new HashMap<>();
		objectMap = new HashMap<Class, Object>();

		pluginVersion = data.getDouble("version");
		pluginName = data.getString("name");
		log.fine("Plugin: " + this);

		DataNode node = data.get("interfaces");
		if(node.isMap())
			addInterfaces(node);
		else if(node.isList()) {
			Iterator<DataNode> intfs_it = node.iterator();
			while (intfs_it.hasNext()) {
				addInterfaces(intfs_it.next());
			}
		}
	}
	private void addInterfaces(DataNode node){
		Iterator<String> intf_it = node.keyIterator();
		while (intf_it.hasNext()) {
			String pluginIntf = intf_it.next();
			String className = node.get(pluginIntf).getString();

			Class intfClass = getClassByName(pluginIntf);
			Class pluginClass = getClassByName(className);
			if (intfClass == null || pluginClass == null)
				log.warning("Plugin interface: " +
						(intfClass==null ? "(Not Available) " : "") + pluginIntf + " --> " +
						(pluginClass==null ? "(Not Available) " : "") + className);
			else
				log.finer("Plugin interface: "+ pluginIntf +" --> "+ className);

			if (intfClass == null || pluginClass == null)
				continue;

			if (!classMap.containsKey(intfClass))
				classMap.put(intfClass, new ArrayList<Class<?>>());
			classMap.get(intfClass).add(pluginClass);
		}
	}
	private static Class getClassByName(String name) {
		try {
			return Class.forName(name);
		}catch (Exception e){
			//log.log(Level.WARNING, null, e); // No need to log, we are handling it
		}
		return null;
	}


	public double getVersion(){
		return pluginVersion;
	}
	public String getName(){
		return pluginName;
	}


	public <T> Iterator<T> getObjectIterator(Class<T> intf){
		if(!classMap.containsKey(intf))
			return Collections.emptyIterator();
		return new PluginObjectIterator<T>(classMap.get(intf).iterator());
	}
	public Iterator<Class<?>> getClassIterator(Class<?> intf){
		if(!classMap.containsKey(intf))
			return Collections.emptyIterator();
		return classMap.get(intf).iterator();
	}

	private <T> T getObject(Class<T> objClass) {
		try {
			if (!objectMap.containsKey(objClass))
				objectMap.put(objClass, objClass.newInstance());
			return (T) objectMap.get(objClass);
		} catch (Exception e) {
			log.log(Level.WARNING, null, e);
		}
		return null;
	}


	public boolean contains(Class<?> intf){
		return classMap.containsKey(intf);
	}

	public String toString(){
		return getName()+"(ver: "+getVersion()+")";
	}



	private class PluginObjectIterator<T> implements Iterator<T>{
		private Iterator<Class<?>> classIt;
		private T currentObj;

		public PluginObjectIterator(Iterator<Class<?>> it) {
			classIt = it;
		}

		@Override
		public boolean hasNext() {
			if(currentObj != null)
				return true;
			while (classIt.hasNext()){
				currentObj = (T)getObject(classIt.next());
				if(currentObj != null)
					return true;
			}
			return false;
		}

		@Override
		public T next() {
			if(!hasNext())
				throw new NoSuchElementException();
			T tmp = currentObj;
			currentObj = null;
			return tmp;
		}

		@Override
		public void remove() {
			throw new RuntimeException("Iterator is ReadOnly");
		}
	}
}