ServiceFactory.java

package com.jqmobile.core.server.service;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.Connection;
import java.sql.SQLException;

import com.jqmobile.core.server.db.DBPool;
import com.jqmobile.core.service.Service;
import com.jqmobile.core.utils.ClassForNameUtil;

/**
 * Manager实例化工厂
 * @author MODI
 *
 * @project com.jiuqi.mobile.core
 * @date 2013年11月15日
 */
public abstract class ServiceFactory {
	private static ServiceFactory mf = new BaseManagerFactory();
	/**
	 * 自定义默认实例化工程。仅限框架底层使用
	 * @param factory void
	 */
	public static void setServiceFactory(ServiceFactory factory){
		mf = factory;
	}
	/**
	 * 实例化Manager
	 * @param c
	 * @return
	 */
	public static <T> T instance(Class<T> c){
		return mf.instanceService(c);
	}
	/**
	 * 实例化Manager
	 * @param c
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public <T> T instanceService(Class<T> c){
		return (T) Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(), new Class<?>[]{c}, getInvocationHandler(c));
	}
	/**
	 * 获得切面代理
	 * @return
	 */
	protected abstract InvocationHandler getInvocationHandler(Class<?> c);
	/**
	 * 获得数据库连接
	 * @return
	 */
	public abstract Connection newConnection();
	//=============================================================
	static final class BaseManagerFactory extends ServiceFactory{

		@Override
		protected InvocationHandler getInvocationHandler(Class<?> c) {
			return new BaseInvocationHandler(c);
		}

		@Override
		public Connection newConnection() {
			try {
				return DBPool.getInstance().getConnection();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			return null;
		}
		
	}
	//=============================================================
	final class BaseInvocationHandler implements InvocationHandler{
		private Class<?> c;
		BaseInvocationHandler(Class<?> c){
			this.c=c;
		}
		@Override
		public Object invoke(Object proxy, Method method, Object[] args)
				throws Throwable {
			long uuid = Thread.currentThread().getId();
			BaseManagerUtil util = new BaseManagerUtil();
			try{
				ServiceUtil.utils.put(uuid, util);
				try{
					Service annotation = c.getAnnotation(Service.class);
					if(null == annotation){
						throw new ServiceAnnotationException(c);
					}
					String impl = annotation.impl();
					Class<?> ci = ClassForNameUtil.forName(impl);
//					Class<?> ci = Class.forName(impl, false, Thread.currentThread().getContextClassLoader());
					Object obj = ci.newInstance();
					//
					try{
						//pre
						if(null != util.getPreAction()){
							util.getPreAction().action();
						}
						Object result = method.invoke(obj, args);
						//succeed
						if(null != util.getSucceedAction()){
							util.getSucceedAction().action();
						}
						util.commit();
						return result;
					}catch(Throwable e){
						util.rollback();
						//exception
						if(null != util.getExceptionAction()){
							util.getExceptionAction().action(e);
						}
						throw e;
					}
					//
				}finally{
					ServiceUtil.utils.remove(uuid);
				}
			}finally{
				util.close();
				//finish
				if(null != util.getFinishAction()){
					util.getFinishAction().action();
				}
			}
		}
	}
	final class BaseManagerUtil extends ServiceUtil{
		private Connection connection;

		public Connection getConnection() {
			if(null == connection) connection = newConnection();
			return connection;
		}
		private void commit() throws Exception{
			if(null != connection) connection.commit();
		}
		private void rollback() throws Exception{
			if(null != connection) connection.rollback();
		}
		private void close() throws Exception{
			if(null != connection) connection.close();
		}
	}
}