usermangerdao.java

这是java的源代码,感觉上是挺不错的哦,要下载赶快来哦,有附加数据库的哦

package ptu.dao;

import java.beans.Statement;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import ptu.db.DBConnection;

public class UserMangerDAO {
	private Connection con = null;//定义一个连接，用来保存所连到的数据库

	private PreparedStatement statement = null;//定义一个邮差，用来保存要执行的命令

	private ResultSet rs = null;//定义一个结果集，用来保存所得到的结果

	//查找数据，如果找到返回true,没找到返回false。作用，用户登录时被调用
	public boolean isExist(String userName, String userPassWord)
			throws Exception {
		boolean exist = false;
		con = DBConnection.getConnection();
		statement = con
		.prepareStatement("SELECT * from  userManger where userName=? and userPassWord=?");
		statement.setString(1, userName);
		statement.setString(2, userPassWord);
		rs = statement.executeQuery();
		if (rs.next()) {
			exist = true;
		}
		DBConnection.closeResultSet(rs);
		DBConnection.closeStatement(statement);
		DBConnection.closeConnection(con);
		return exist;
	}
//插入一条新的数据，作用：用户注册时被调用
	public void save(String userName, String userPassWord) throws Exception {
		if (isExist(userName, userPassWord) == false) {
			con = DBConnection.getConnection();
			statement = con
					.prepareStatement("insert into userManger values(?,?)");
			statement.setString(1, userName);
			statement.setString(2, userPassWord);
			statement.execute();

		}
		DBConnection.closeStatement(statement);
		DBConnection.closeConnection(con);
	}
//修改数据库内容，作用：修改用户密码时被调用
	public void upDate(String userName, String userPassWord, String newPassWord)
			throws Exception {
		con = DBConnection.getConnection();
		statement = con
				.prepareStatement("update userManger set userPassWord=? where userName=? and userPassWord=?");
		statement.setString(1, newPassWord);
		statement.setString(2, userName);
		statement.setString(3, userPassWord);
		statement.execute();
		DBConnection.closeStatement(statement);
		DBConnection.closeConnection(con);
	}
//删除一条数据，作用：删除用户时被调用
	public void delete(String userName) throws Exception {
		con = DBConnection.getConnection();
		statement = con.prepareStatement("delete userManger where userName=?");
		statement.setString(1, userName);
		statement.execute();
		DBConnection.closeStatement(statement);
		DBConnection.closeConnection(con);
	}

}