jsp+javaBean+servlet+mysql完整的实现一个登录功能

package com.arvin.servlet; import java.io.IOException; import java.sql.ResultSet; import java.sql.SQLException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.annotation.WebServlet; import com.arvin.db.ConnDB; @WebServlet("/LoginServlet") public class LoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; public LoginServlet() { super(); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub String db_username = null; String db_password = null; String key = request.getParameter("username"); String value = request.getParameter("password"); try { //获得连接 ConnDB.getConnection(); String sql = "select * from t_userinfo"; ResultSet rs = ConnDB.excuteQuery(sql); while(rs.next()){ db_username = rs.getString("username"); db_password = rs.getString("password"); System.out.println("shujuku"+db_username+","+db_password); System.out.println("yemian"+key+","+value); if((db_username.equals(key))&&(db_password.equals(value))){ System.out.println("匹配成功"); request.setAttribute("name", key); request.getRequestDispatcher("/success.jsp").forward(request, response); break; } if((!(db_username.equals(key))||!(db_password.equals(value)))&&(rs.next() == false)){ request.getRequestDispatcher("/failure.jsp").forward(request, response); } } } catch (Exception e) { // TODO 自动生成的 catch 块 e.printStackTrace(); } // if((db_username.equals(key))&&(db_password.equals(value))){ // request.setAttribute("name", key); // request.getRequestDispatcher("/success.jsp").forward(request, response); // }else{ // request.getRequestDispatcher("/success.jsp").forward(request, response); //} } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub doGet(request,response); } }