proxyinstancevisitable.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.bussinessproxy.web;

import com.jdon.bussinessproxy.TargetMetaDef;

import java.lang.reflect.Proxy;
import com.jdon.util.Debug;
import com.jdon.bussinessproxy.AopClient;
import com.jdon.bussinessproxy.cache.*;

public class ProxyInstanceVisitable implements Visitable {

  private final static String module = ProxyInstanceVisitable.class.getName();

  private AopClient aopClient;
  private TargetMetaDef targetMetaDef;
  public ProxyInstanceVisitable(TargetMetaDef targetMetaDef,
                                AopClient aopClient) {
    this.aopClient = aopClient;
    this.targetMetaDef = targetMetaDef;
  }

  public Object accept(ComponentCacheVisitor visitor) {
    return createDynamicProxy(visitor);
  }

  public Object createDynamicProxy(ComponentCacheVisitor cm) {
    Object dynamicProxy = null;
    try {
      WebInvocationHandler handler = createInvocationHandler(cm);

      ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
      Class serviceClass = classLoader.loadClass(targetMetaDef.getClassName());
      dynamicProxy =
          Proxy.newProxyInstance(
          classLoader,
          new Class[] {serviceClass}
          ,
          handler);
    } catch (Exception ex) {
      Debug.logError(" Proxy.newProxyInstance error:" + ex, module);

    } catch (Throwable ex) {
      Debug.logError(" Proxy.newProxyInstance error:" + ex, module);

    }
    return dynamicProxy;
  }

  private WebInvocationHandler createInvocationHandler(ComponentCacheVisitor cm) {
    WebInvocationHandler handler = new WebInvocationHandler(targetMetaDef,
        aopClient);
    handler.setVisitor(cm);
    return handler;
  }

}