SSH复习题(6)

@Entity

public class User { @Id @GeneratedValue private int id; private String username; private String password; //setter方法和getter方法略去 }

//类UserAction package com.action;

import com.opensymphony.xwork2.ActionSupport; import com.model.User;

import com.service.UserManager;

public class UserAction extends ActionSupport { private String username; private String password; private String password2; UserManager um = new UserManager(); //setter方法和getter方法略去 @Override public String execute() throws Exception { User u = new User(); u.setUsername(username); u.setPassword(password); if(um.exists(u)) { return \ } um.add(u); return \ } }

//类UserManager package com.service;

import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import com.model.User; public class UserManager {

//实现判断用户是否存在功能，部分代码已经完成。 public boolean exists(User u) throws Exception { Class.forName(\ Connection conn = DriverManager.getConnection

(\ String sq=“select * from user where username=？andpassword？”； Prepared。Statement ps=null； Boolean flag=false;

Ps.conn.preparedStatement(sql); ps.setString(1.u.getUsername()); ps.setString(2.u.getPassword()); Result rs=ps.exectureQuery(); While*rs.next()){ Flag=true;} re.close(); ps.close(); conn.close(); return flag; } //实现将用户信息添加到数据库中的功能，部分代码已经完成。 public void add(User u) throws Exception { Class.forName(\ Connection conn = DriverManager.getConnection (\

String sql=”insert into user(username,password)values(?,?)”; ps.setString().u.getUsername(); ps.setString(2,u.getPassword()); ps.executeupdate(); ps.closed(); conn.close(); } }