基于struts的登陆注册源码

package org.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.model.User; public class DbService { //添加注册用户 public void addUser(User user){ Connection connection=DbConnection.getConnection(); PreparedStatement ps=null; String sql="insert into simple_tb (username,password) values(?,?)"; try{ ps=connection.prepareStatement(sql); System.out.println("\n======="+user.getUsername()); System.out.println("\n======="+user.getPassword()); ps.setString(1, user.getUsername());//将数据写入数据库 ps.setString(2, user.getPassword()); ps.executeUpdate(); //Executes the SQL statement in this PreparedStatement object; }catch (SQLException e) { // TODO: handle exception e.printStackTrace(); } } //查找用户是否存在 public User hasUser(String username,String password){ User user=new User(); Connection connection=DbConnection.getConnection(); PreparedStatement ps=null; ResultSet rs=null; String sql="select * from simple_tb where username=? and password=?"; try { ps=connection.prepareStatement(sql); ps.setString(1, username); //key-value中的key对应着sql语句中的第几个“？” ps.setString(2, password); rs=ps.executeQuery(); /*Executes the SQL query in this PreparedStatement object and * returns the ResultSet object generated by the query.*/ if(rs.next()){ //从第一行数据开始查找 System.out.println("\n======="+rs.getString(1)); System.out.println("\n======="+rs.getString(2)); user.setUsername(rs.getString("username"));//将查找到的数据返回 user.setPassword(rs.getString("password")); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ DbConnection.closeConnection(rs, ps, connection); } return user; } //查找用户名是否已经被注册 public Boolean hasSameUser(String username){ String name=null; Connection connection=DbConnection.getConnection(); PreparedStatement ps=null; ResultSet rs=null; String sql="select * from simple_tb where username=?"; try { ps=connection.prepareStatement(sql); ps.setString(1, username); rs=ps.executeQuery(); if(rs.next()){ name=rs.getString("username"); if(name.equals(username)) return true; else return false; } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ DbConnection.closeConnection(rs, ps, connection); } return false; } }