最近有人问加哥怎么连接数据库,和数据库建立连接。下面给大家分享一下JDBC连接数据库的模版方法。加哥是以mysql为例,若是其他数据库替换层其他的即可。
步骤:
1.引入数据库架包
2.加载驱动
3.创建连接
4.进行相应数据库操作
5.关闭数据库连接。
下面直接给大家上代码:
package org.util; import java.sql.*; public class BaseDao { //驱动 private static String driver = "com.mysql.jdbc.Driver"; private static String url = "jdbc:mysql://127.0.0.1:3306/mytest?characterEncoding=utf-8&serverTimezone=Asia/Shanghai"; //用户名 private static String username = "root"; //密码 private static String pwd = "123456"; /** * 创建连接 * @return */ public static Connection getConnection(){ Connection connection=null; //加载驱动 try { Class.forName(driver); } catch (ClassNotFoundException e) { e.printStackTrace(); } //建立连接获取Connection对象 try { connection= DriverManager.getConnection(url,username,pwd); } catch (SQLException e) { e.printStackTrace(); } return connection; } /** * 关闭链接 * @param connection * @param statement * @param resultSet */ public static void closeAll(Connection connection, Statement statement, ResultSet resultSet){ try { if(resultSet!=null){ resultSet.close(); } if(statement!=null){ statement.close(); } if (connection!=null){ connection.close(); } } catch (SQLException e) { e.printStackTrace(); } } /** * 执行增、删、改的方法 * @param sql * @return */ public static int execute(String sql){ //获取链接 Connection connection=getConnection(); int flag=0; try { //创建Statement对象 Statement statement=connection.createStatement(); //执行sql语句 flag=statement.executeUpdate(sql); //关闭链接 closeAll(connection,statement,null); } catch (SQLException e) { e.printStackTrace(); } return flag; } /* 测试 */ public static void main(String[] args) { String sql = "SELECT * FROM bs_structure WHERE id = 1688350472671"; Connection connection = getConnection(); Statement statement = null; try { statement= connection.createStatement(); ResultSet resultSet = statement.executeQuery(sql); while(resultSet.next()){ String typename = resultSet.getString(3); System.out.println("类别名称:"+typename); } } catch (SQLException e) { e.printStackTrace(); } } }