Jdbc链接数据库使用配置文件

Posted 2020-09-17 情似雨餘黏地絮

这种方式是比较传统的链接方式，比较适合初学者

首先在配置文件中写入你要使用的相关数据

db.properties

 driverName = com.mysql.jdbc.Driver
 url = jdbc:mysql://localhost:3306/staff
 user = root
 password = 123456

然后是一个链接数据库的JDBC工具类，之后你要链接数据库的时候只需要JdbcUtil.getConnection()就可以获取链接

JdbcUtil.java

package com.xinzhi.util;

import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class JdbcUtil {
    public static Connection getConnection() {
        Connection connection = null;
        Properties properties = new Properties();
        InputStream inputStream = JdbcUtil.class.getResourceAsStream("/db.properties");//用流的方式读取配置文件
        try {
            properties.load(inputStream);
            String driverName = properties.getProperty("driverName");//获取配置文件中的相关数据
            String url = properties.getProperty("url");
            String user = properties.getProperty("user");
            String password = properties.getProperty("password");
            Class.forName(driverName);//加载驱动器
            connection = DriverManager.getConnection(url, user, password);//链接
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return connection;
    }
　　/**
　　* 关闭开启的相关事件
　　**/

    public static void close(Statement statement, Connection connection, ResultSet resultSet) {
        if (resultSet != null) {
            try {
                resultSet.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            resultSet = null;
        }
        if (statement != null) {
            try {
                statement.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            statement = null;
        }
        if (connection != null) {
            try {
                connection.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            connection = null;
        }
    }
}