methodinvokerutil.java

一个非常好的FRAMWRK!是一个外国组织做的!不!

/*
 * Copyright 2003-2005 the original author or authors.
 * 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.reflection;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.rmi.Remote;

import javax.ejb.EJBObject;
import javax.rmi.PortableRemoteObject;

import org.aopalliance.aop.AspectException;

import com.jdon.bussinessproxy.target.TargetServiceFactory;
import com.jdon.container.access.TargetMetaRequest;
import com.jdon.container.finder.ComponentKeys;
import com.jdon.container.visitor.ComponentVisitor;
import com.jdon.util.Debug;

/**
 * tools for method invoke
 * @author <a href="mailto:[e-mail]">banq </a>
 *  
 */
public class MethodInvokerUtil {
    private final static String module = MethodInvokerUtil.class.getName();

    /**
     * the service execute by method reflection
     * 
     * @param method
     * @param targetObj
     * @param p_args
     * @return
     * @throws Throwable
     */
    public Object execute(Method method, Object targetObj, Object[] p_args) throws Throwable {
        try {
            if ((method == null) || (targetObj == null))
                Debug.logError(" no method or target, please check your configure", module);
            if (p_args == null)
                p_args = new Object[0];
            Object result = method.invoke(targetObj, p_args);
            Debug.logVerbose(" method invoke successfully ", module);
            return result;
        } catch (IllegalArgumentException iex) {
            Debug.logError(" method invoke IllegalArgumentException: " + iex, module);
            throw new Throwable(" check your interceptor : ", iex);
        } catch (InvocationTargetException ex) {
            String errorInfo = " method "+ method.getName() +" run error: " + ex.getTargetException() + " check your method's code! or use try..catch ";
            Debug.logError(errorInfo, module);
            throw new Throwable(errorInfo);
        } catch (IllegalAccessException ex) {
            Debug.logError(" method invoke IllegalAccessException: " + ex, module);            
            throw new Throwable("access method:" + method + " " + ex, ex);
        } catch (Exception ex) {
            Debug.logError(" method invoke error: " + ex, module);
            throw new Throwable(" method invoke error: " + ex);
        }

    }

    /**
     * if target service is ejb object, cache it,
     * so this function can active stateful session bean.
     * 
     * @param targetServiceFactory
     * @param targetMetaDef
     * @return
     * @throws Exception
     */
    public Object createTargetObject(TargetServiceFactory targetServiceFactory, TargetMetaRequest targetMetaRequest) {
        Debug.logVerbose(" now getTargetObject by visitor ", module);
        Object targetObjRef = null;
        try {
            if (targetMetaRequest.getTargetMetaDef().isEJB()) { //cache the ejb object
                ComponentVisitor cm = targetMetaRequest.getComponentVisitor();
                targetMetaRequest.setVisitableName(ComponentKeys.TARGETSERVICE_FACTORY);
                Debug.logVerbose(ComponentKeys.TARGETSERVICE_FACTORY + " in action (cache)", module);
                targetObjRef = cm.visit(targetMetaRequest);
            } else {
                Debug.logVerbose(" not active targer service instance cache !!!!", module);
                targetObjRef = targetServiceFactory.create(targetMetaRequest.getTargetMetaDef());
            }
        } catch (Exception e) {
            Debug.logError("createTargetObject error: " + e, module);
        }
        return targetObjRef;
    }

    /**
     * 如果参数中有remote EJB，需要从远程序列化过来这些参数
     *  
     */
    public Object[] narrowArgs(Object[] p_args) {
        if (p_args == null)
            return null;
        int length = p_args.length;
        Object[] result = new Object[length];
        for (int i = 0; i < length; i++) {
            if (p_args[i] instanceof Remote)
                result[i] = PortableRemoteObject.narrow(p_args[i], EJBObject.class);
            else
                result[i] = p_args[i];
        }
        return result;
    }

}