joinpointfactory.java

Java/J2EE框架Jdon-Framework系统的Sample

/**
 * Copyright 2005 Jdon.com
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

package com.jdon.aop.joinpoint;

import org.aopalliance.aop.Advice;
import org.aopalliance.intercept.MethodInvocation;
import com.jdon.bussinessproxy.MethodInvoker;
import com.jdon.bussinessproxy.cache.ComponentCacheVisitor;
import com.jdon.bussinessproxy.TargetMetaDef;

import com.jdon.util.Debug;
import java.util.Collection;
import com.jdon.aop.*;
import com.jdon.bussinessproxy.meta.MethodMetaArgs;


/**
 * 生成Joinpoint工厂类
 *
 * 创建ProxyMethodInvocation实例，ProxyMethodInvocation生命周期
 * 是Request，在每个Request中，以每个方法为Key，逐个访问interceptors集合
 * 中的每个拦截器

 * @author banq
 * @version 1.0
 */
public class JoinpointFactory implements Advisor {
  private final static String module = JoinpointFactory.class.getName();

  private Collection interceptors ;
  protected MethodInvoker methodInvoker;
  public Collection getInterceptors() {
    return interceptors;
  }

  public JoinpointFactory(Collection interceptors, MethodInvoker methodInvoker) {
     this.interceptors = interceptors;
     this.methodInvoker = methodInvoker;
  }

  /**
   * 每次动态代理的方法调用激活本方法
   *
   *
   * @param targetMethodInvoker MethodInvoker
   * @param session HttpSession
   * @param targetMetaDef TargetMetaDef
   * @param m Method
   * @param arguments Object[]
   * @throws Exception
   * @return MethodInvocation
   */
  public MethodInvocation createJoinpoint(ComponentCacheVisitor cm,
                                          TargetMetaDef targetMetaDef) throws
      Exception {
    Debug.logVerbose(" enter  createJoinpoint ", module);
    MethodMetaArgs methodMetaDef = targetMetaDef.getMethodMetaArgs();
    ProxyMethodInvocation proxyMethodInvocation = new
         ProxyMethodInvocation(cm, methodInvoker, interceptors, targetMetaDef);

      //每次调用的是同一个proxyMethodInvocation
      //但是不同的是参数 和指针
      proxyMethodInvocation.setArguments(methodMetaDef.getArgs());
      proxyMethodInvocation.resetIterator();
    return proxyMethodInvocation;
  }


  public Advice getAdvice() {
    return null;
  }

}