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package com.text.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import com.sun.corba.se.spi.servicecontext.UEInfoServiceContext; import com.text.entity.User; import com.text.util.JdbcUtil; import com.text.util.PropertiesUtil; /* * UserDao *层操作User表 */ public class UserDao { //对数据库user表的用户名与密码核对的方法 public User login(String username,String pwd){ Connection connection = null; PreparedStatement preparedStatement = null; ResultSet resultSet = null; User user = null; try{ //连接数据库 connection =JdbcUtil.getJdbcUtil().getConnection(); //将此连接的自动提交模式设置为false connection.setAutoCommit(false); //mysql语句检测用户名与密码（decode(?,?)解密） StringBuffer stringBuffer=new StringBuffer(" select id,username,pwd,realname from user where username = ? and decode(pwd,?)=? "); //存储用户名与密码，需要时调用 preparedStatement=connection.prepareStatement(stringBuffer.toString()); preparedStatement.setString(1, username); preparedStatement.setString(3, pwd); //用PropertiesUtil读取prepareStatement存储的mysql语句(密匙) preparedStatement.setString(2, PropertiesUtil.getPropertiesUtil().getValue("mykey")); //查询结果 resultSet=preparedStatement.executeQuery(); //遍历信息 if(resultSet.next()){ user=new User(); user.setId(resultSet.getInt("id")); user.setUsername(resultSet.getString("username")); user.setPwd(resultSet.getString("pwd")); user.setRealname(resultSet.getString("realname")); } //user不为空时 if(user!=null){ //mysql语句检测用户名是否在线(在线=1) StringBuffer onLineBuffer=new StringBuffer(" update user set isonline = 1 where username = ? "); //存储用户名与密码，需要时调用 preparedStatement=connection.prepareStatement(onLineBuffer.toString()); preparedStatement.setString(1, user.getUsername()); preparedStatement.executeUpdate(); } //放此 Connection 对象当前持有的所有数据库锁 connection.commit(); }catch(Exception e){ try { //返回Connection 对象 connection.rollback(); } catch (SQLException e1) { e1.printStackTrace(); } e.printStackTrace(); }finally{ //关闭连接 JdbcUtil.getJdbcUtil().closeConnection(resultSet, preparedStatement, connection); } return user; } //检测数据库user表用户名是否重叠的方法 public User getByUsername(String username){ Connection connection = null; PreparedStatement preparedStatement = null; ResultSet resultSet = null; User user = null; try{ //连接数据库 connection =JdbcUtil.getJdbcUtil().getConnection(); //mysql语句检测用户名 StringBuffer stringBuffer=new StringBuffer(" select id,username,pwd,realname from user where username = ? "); //存储用户名，需要时调用 preparedStatement=connection.prepareStatement(stringBuffer.toString()); preparedStatement.setString(1, username); //查询结果 resultSet=preparedStatement.executeQuery(); //遍历信息 if(resultSet.next()){ user=new User(); user.setId(resultSet.getInt("id")); user.setUsername(resultSet.getString("username")); user.setPwd(resultSet.getString("pwd")); user.setRealname(resultSet.getString("realname")); } }catch(Exception e){ e.printStackTrace(); }finally{ //关闭连接 JdbcUtil.getJdbcUtil().closeConnection(resultSet, preparedStatement, connection); } return user; } //对数据库user表添加新用户的方法 public void insertUser(User user){ Connection connection = null; PreparedStatement preparedStatement = null; try{ //连接数据库 connection =JdbcUtil.getJdbcUtil().getConnection(); //mysql语句增加新用户 StringBuffer stringBuffer=new StringBuffer(" insert into user (username,pwd,realname,photo) values (?,encode(?,?),?,?) "); //存储新用户，需要时调用(用户名，密码，真实姓名，图片) preparedStatement=connection.prepareStatement(stringBuffer.toString()); preparedStatement.setString(1, user.getUsername()); preparedStatement.setString(2, user.getPwd()); //用PropertiesUtil读取prepareStatement存储的mysql语句(密匙) preparedStatement.setString(3, PropertiesUtil.getPropertiesUtil().getValue("mykey")); preparedStatement.setString(4, user.getRealname()); preparedStatement.setString(5, user.getPhoto()); //增加新用户 preparedStatement.executeUpdate(); }catch(Exception e){ e.printStackTrace(); }finally{ //关闭连接 JdbcUtil.getJdbcUtil().closeConnection(null, preparedStatement, connection); } } //得到好友列表集的方法 public List<User> getUserList(){ Connection connection = null; PreparedStatement preparedStatement = null; ResultSet resultSet = null; List<User> users = null; try{ //连接数据库 connection =JdbcUtil.getJdbcUtil().getConnection(); //mysql语句检测用户表 StringBuffer stringBuffer=new StringBuffer(" select id,username,pwd,realname,photo,isonline from user "); //存储用户表，需要时在数据库调用 preparedStatement=connection.prepareStatement(stringBuffer.toString()); //查询结果 resultSet=preparedStatement.executeQuery(); //如果返回的结果集不为空，则new一个好友列表集 if(!resultSet.wasNull()){ users=new ArrayList<User>(); } //遍历信息 while(resultSet.next()){ User user=new User(); user.setId(resultSet.getInt("id")); user.setUsername(resultSet.getString("username")); user.setRealname(resultSet.getString("realname")); user.setPhoto(resultSet.getString("photo")); user.setIsonline(resultSet.getInt("isonline")); //将遍历的好友信息添加到好友列表集里 users.add(user); } }catch(Exception e){ e.printStackTrace(); }finally{ //关闭连接 JdbcUtil.getJdbcUtil().closeConnection(resultSet, preparedStatement, connection); } return users; } //退出的方法 public void exit(String username){ Connection connection = null; PreparedStatement preparedStatement = null; try{ //连接数据库 connection =JdbcUtil.getJdbcUtil().getConnection(); //mysql语句检测用户表 StringBuffer sqlBuffer=new StringBuffer(" update user set isonline = 0 where username = ? "); //存储用户表，需要时在数据库调用 preparedStatement=connection.prepareStatement(sqlBuffer.toString()); preparedStatement.setString(1, username); //更新结果 preparedStatement.executeUpdate(); }catch(Exception e){ e.printStackTrace(); }finally{ //关闭连接 JdbcUtil.getJdbcUtil().closeConnection(null, preparedStatement, connection); } } }