Java JDBC(Maven工程)

概述

JDBC(Java Data Base Connectivity) 是一种用于执行SQL的Java API,可以为多种关系型数据库提供统一访问，它由一组Java语言编写的类和接口组成，是Java访问数据库的标准规范。

准备

创建MySQL表名worker，字段id, name, age, jobpom.xml添加依赖 <dependencies> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.18</version> </dependency> </dependencies>

 

两种执行SQL的方法

package test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.sql.PreparedStatement; public class testMysql { public static void main(String[] args) { Connection conn = null; Statement stmt = null; ResultSet rs = null; // mysql8.0以上版本 String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver"; String URL = "jdbc:mysql://localhost:3306/test?user=root&password=123456&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC"; try{ Class.forName(JDBC_DRIVER); // 加载驱动 conn = DriverManager.getConnection(URL); // 建立连接 stmt = conn.createStatement(); // 创建statement对象，用来执行sql String values = "(\"xiaozhao\", 21, \"develepment\")," + "(\"xiaoqian\", 22, \"develepment\")," + "(\"xiaosun\", 23, \"develepment\")," + "(\"xiaoli\", 24, \"develepment\")"; stmt.execute("insert into worker (name, age, job) values " + values); /** // 通过PreparedStatement对象执行预编译 SQL语句 String sql = "select * from worker where id = ?"; PreparedStatement preparedStatement = conn.prepareStatement(sql); preparedStatement.setString(1, "5"); // 设置参数：第一个参数表示第几个占位符，第二个参数表示具体值，注意参数类型和方法对应 rs = preparedStatement.executeQuery(); while(rs.next()){ String id = rs.getString("id"); String name = rs.getString("name"); Integer age = rs.getInt("age"); String job = rs.getString("job"); System.out.println(String.format("%s %s %d %s", id, name, age, job)); } */ }catch(ClassNotFoundException e){ System.out.println("加载驱动异常"); e.printStackTrace(); }catch(SQLException e){ System.out.println("数据库异常"); e.printStackTrace(); }finally{ // 关闭资源 System.out.println("执行结束"); try { if (stmt != null) { stmt.close(); } }catch(SQLException e){ e.printStackTrace(); } try{ if (conn != null){ conn.close(); } }catch(SQLException e){ e.printStackTrace(); } } } }