有么有Java大神解决一下，关于servlet的跳转问题，新手，没c币，求帮忙

Question

这是代码
package com.neuedu.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.neuedu.business.service.UserService;

public class UserZhuCe extends HttpServlet {

/**
 * The doPost method of the servlet. <br>
 *
 * This method is called when a form has its tag value method equals to post.
 * 
 * @param request the request send by the client to the server
 * @param response the response send by the server to the client
 * @throws ServletException if an error occurred
 * @throws IOException if an error occurred
 */
public void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    String userName=request.getParameter("userName");
    String passWord=request.getParameter("passWord");
    String age=request.getParameter("age");
    String sex=request.getParameter("sex");
    UserService userService=new UserService();
    userService.registration(userName, passWord, age, sex);
    out.flush();
    out.close();
    request.getRequestDispatcher("../Admin/main.jsp").forward(request, response);

}

}

这是异常
Servlet.service() for servlet [UserZhuCe] in context with path [/My12306] threw exception
java.lang.IllegalStateException: Cannot forward after response has been committed
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:348)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at com.neuedu.servlet.UserZhuCe.doPost(UserZhuCe.java:38)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at com.neuedu.utils.SessionInterceptor.doFilter(SessionInterceptor.java:39)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:957)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:620)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2476)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2465)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:619)

Answer 1

public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
// PrintWriter out = response.getWriter();
String userName=request.getParameter("userName");
String passWord=request.getParameter("passWord");
String age=request.getParameter("age");
String sex=request.getParameter("sex");
UserService userService=new UserService();
userService.registration(userName, passWord, age, sex);
// out.flush();
// out.close();
request.getRequestDispatcher("../Admin/main.jsp").forward(request, response);

}

输出和转发动作冲突了，二者选其一