import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//响应自己写的报错
/**
 * Servlet implementation class SendErrorServlet
 */
@WebServlet("/SendErrorServlet")
public class SendErrorServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public SendErrorServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(request, response);
	}
	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	
		response.setContentType("text/html");
		response.setCharacterEncoding("UTF-8");
//		获取输入流
		PrintWriter out =response.getWriter();
//		设置响应状态码以及响应状态信息
		response.sendError(response.SC_NOT_FOUND,"对不起 亲爱的 找不到你了!");
	}
}
原文:http://www.cnblogs.com/sdswl/p/5801232.html