filter 过滤出现 getOutputStream() has already been called for this response

2011-04-16 10:16:11 449 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

uni踩坑笔记 - 离线打包调起微信分享后从微信返回APP时黑屏 apk能成功调起微信并进行分享操作，但分享完成后点击回到应用后应用出现黑屏的情况，并在约3-5秒后自动重启。阅读详情

number.jsp



<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<link rel="stylesheet"

      href="/why/css/my.css"

      type="text/css"/>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

<div class="red"> set </div>

 <c:set var="session" value="i am sseison" scope="session"></c:set>

 <c:set var="application" value="i am application" scope="application"></c:set>

 session${session}<br/>

 context${applicationScope.application}

 <c:import url="http://en.wikipedia.org/wiki/Google"></c:import>

</body>

</html>

web.xml



		<filter-name>changeFilter</filter-name>

		<filter-class>my.ChangeFilter</filter-class>

</filter>

	<filter-mapping>

		<filter-name>changeFilter</filter-name>

		<url-pattern>*</url-pattern>

	</filter-mapping><!--changeFilter2 监视 all --><jsp-config>

	<taglib>

ChangeFilter.java

package my;



import java.io.IOException;

import java.io.PrintWriter;



import javax.servlet.*;

import javax.servlet.http.*;



public class ChangeFilter implements Filter{

	ResponseWrapper response;

	String goal;

	@Override

	public void destroy() {

		// TODO Auto-generated method stub

		

	}



	@Override

	public void doFilter(ServletRequest arg0, ServletResponse arg1,

			FilterChain arg2) throws IOException, ServletException {

		// TODO Auto-generated method stub

		response=new ResponseWrapper((HttpServletResponse )arg1);

		arg2.doFilter(arg0, response );

		change(arg0);

		PrintWriter out=arg1.getWriter();

		out.write(goal);

		out.close();

		

	}



	@Override

	public void init(FilterConfig arg0) throws ServletException {

		// TODO Auto-generated method stub

		

	}

  private void change(ServletRequest arg0){

	  goal=(String)arg0.getServletContext().getInitParameter("newName"); 

	  if(goal!=null){

		  goal=response.toString().replaceAll("google", goal);

	  }else{

		  goal=response.toString();

	  }

  }

}

运行后出现

java.lang.IllegalStateException: getOutputStream() has already been called for this response
at org.apache.catalina.connector.Response.getWriter(Response.java:636)
at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:205)
at my.ChangeFilter.doFilter(ChangeFilter.java:24)

而且没有将那个网页的 google替换掉

我怀疑是 <c:import url="http://en.wikipedia.org/wiki/Google"></c:import>

没有经过过滤

该如何修改是好