JAVA JDBC的单表查询通用dao层代码实现

获取数据库连接对象代码实

package com.eduask.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DBUtil {
	
	private static Connection conn = null;
	private static String url = "jdbc:mysql://localhost:3306/parttime";//parttime是数据库名字
	private static String driver = "com.mysql.jdbc.Driver";
	
	public static Connection getConnection(){
		
		if (conn == null) {
			try {
				Class.forName(driver);
				conn = DriverManager.getConnection(url,"root","root");//url,用户名，密码
			} catch (ClassNotFoundException e) {
				e.printStackTrace();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		return conn;
	}	
	public static void main(String[] args) {
		//System.out.println(DBUtil.getConnection()+"dcsv");
	}
}

下面是公共的dao层代码实现

package com.eduask.util;

import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.Prepared