Struts2 Exception拦截 HTTP请求与Ajax请求

Struts.xml配置：

	<package name="publicPackage" extends="json-default">

		<interceptors>
			<!-- seven -->
			<interceptor name="exceptionInterceptor" class="org.vbs.front.common.intercept.ExceptionInterceptor"></interceptor>
				
			<interceptor-stack name="userStack">
				<!-- seven -->
				<interceptor-ref name="exceptionInterceptor"></interceptor-ref>
				<interceptor-ref name="defaultStack"></interceptor-ref>
			</interceptor-stack>
			
		</interceptors>
		
		<default-interceptor-ref name="userStack"></default-interceptor-ref>
		
		<global-results>
			<result name="exception" type="json">
      			　　<param name="root">exceptionResult</param>
　　　　　　　　　　　　　　</result>
		</global-results>
		
	</package>

　　

Interceptor：

package org.vbs.front.common.intercept;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.HashMap;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;
import org.apache.struts2.ServletActionContext;
import org.apache.struts2.StrutsStatics;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;
import com.opensymphony.xwork2.util.ValueStack;

/*
 * seven
 * 异常获取拦截器，在action中将exception抛出，
 * 			   若一般请求则会跳转到dennied页面，
 * 			   若为ajax请求，则会返回json数据 {"success":"false","message":"抛出的错误信息" }
 * 
 */
public class ExceptionInterceptor implements Interceptor {

	@Override
	public void destroy() {
		// TODO Auto-generated method stub

	}

	@Override
	public void init() {
		// TODO Auto-generated method stub

	}

	@Override
	public String intercept(ActionInvocation invocation) throws Exception {
		// TODO Auto-generated method stub
		String result = null; // Action的返回值
		try {
			// 运行被拦截的Action,期间如果发生异常会被catch住
			result = invocation.invoke();
			return result;
		} catch (Exception e) {
			/**
			 * 处理异常
			 */
			String errorMsg = "出现错误信息，请查看日志！";
			/**
			 * log4j记录日志
			 */
			Logger log = Logger.getLogger(invocation.getAction().getClass());
			log.error(errorMsg, e);
			
			HttpServletRequest request = ServletActionContext.getRequest();
			HttpServletResponse response = ServletActionContext.getResponse(); 
			//分ajax请求与普通请求
			if (request.getHeader("accept").indexOf("application/json") > -1
		             || (request.getHeader("X-Requested-With")!= null && request.getHeader("X-Requested-With").indexOf("XMLHttpRequest") > -1)) {
				/* seven
				 * ajax返回json
				 * 数据格式为 {"success":"false",
				 *         "message":"exception信息" }
				 */
		        System.out.println("Ajax请求回应(exception)");
		        ValueStack stack = invocation.getStack();
		        HashMap<String, Object> exceptionResult = new HashMap<String, Object>();
		        stack.set("exceptionResult", exceptionResult);	
		        exceptionResult.put("success", "false");
		        StringWriter sw = new StringWriter(); 
		        PrintWriter pw = new PrintWriter(sw);
		        e.printStackTrace(pw);
		        exceptionResult.put("message", sw.getBuffer().toString());
		        return "exception";
		     }
		     else{//如果是普通请求
		    	 System.out.println("正常请求回应(exception)");
		    	 return "denied";
		    }
		}
	}

}

　　

 

ajax请求：

$.ajax({
			url : "subjectMaintenance!toCreateSubjectMaintenance.action",
			data : $("#createSubject_queryForm").serialize(),
			type : "post",
			success : function(data) {
				hidemask();
				if(data.success=="false"){
					$.messager.alert(selectLang("提示","提示","tip"), selectLang("创建失败！","創建失敗！","Create fail!"));
				}else{
					
				}
			}
		});