HTTP Status 500
package package1;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import javax.servlet.ServletConfig;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class RegisterProcessAction
*/
public class RegisterProcessAction extends HttpServlet {
private static final long serialVersionUID = 1L;
private Connection cn = null;
private String drivername = null;
private String url = null;
private String user = null;
private String password = null;
public void init(ServletConfig config) throws ServletException
{
super.init(config);
drivername = config.getInitParameter("drivername");
url = config.getInitParameter("url");
try{
Class.forName(drivername);
cn = DriverManager.getConnection(url,user,password);
}catch(Exception e){
System.out.println("取得数据库连接错误："+e.getMessage());
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String userid = request.getParameter("userid");
String password = request.getParameter("password");
String repassword = request.getParameter("repassword");
String name = request.getParameter("name");
if(userid==null||userid.trim().length()==0){
response.sendRedirect("register.jsp");
}
if(password==null||password.trim().length()==0){
response.sendRedirect("register.jsp");
}
if(repassword==null||repassword.trim().length()==0){
response.sendRedirect("register.jsp");
}
if(!password.equals(repassword)){
response.sendRedirect("register.jsp");
}
if(name!=null&&name.trim().length()>0){
name = new String(name.getBytes("UTF-8"));
}
String sql = "insert into register(userid,name,password)values(?,？,？)";
try{
PreparedStatement ps = cn.prepareStatement(sql);
ps.setString(1, userid);
ps.setString(2, name);
ps.setString(3, password);
ps.executeUpdate();
ps.close();
response.sendRedirect("success.jsp");
}catch(Exception e){
System.out.println("错误："+e.getMessage());
response.sendRedirect("register.jsp");
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
public void destroy(){
super.destroy();
try{
cn.close();
}catch(Exception e){
System.out.println("关闭数据库错误："+e.getMessage());
}
}
}
运行之后老是出现HTTP Status 500 - Cannot call sendRedirect() after the response has been committed
--------------------------------------------
type Exception report
message Cannot call sendRedirect() after the response has been committed
description The server encountered an internal error (Cannot call sendRedirect() after the response has been committed) that prevented it from fulfilling this request.
exception
java.lang.IllegalStateException: Cannot call sendRedirect() after the response has been committed
org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:483)
package1.RegisterProcessAction.doGet(RegisterProcessAction.java:45)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.29 logs.
求高手解答！
[解决办法]
500是服务器错误，一般是连接不上数据库或配置哪里写错了，你先注释掉
package1.RegisterProcessAction.doGet(RegisterProcessAction.java:45)这里的代码，然后一步一步的调错试试。
[解决办法]
在每个response.sendRedirect() 调用后面加上return
[解决办法]
ActionForward forward = new ActionForward("XXX.jsp");
forward.setRedirect(true);
return forward ;
protected void doGet()最好不要定义void类型的，改成ActionForward 类型，像上面那样重定向。
[解决办法]
