分布式事务【2】【JDBC事务演示】

分布式事务【1】【数据库事务演示】: https://yuanyu.blog.csdn.net/article/details/104218792

/**
 * 张三给李四转账100元
 */
@Test
public void transfer() throws SQLException {
    Connection conn = null;
    Statement stmt = null;
    try {
        conn = JDBCConnectionUtil.getConnection();
        // 将自动提交设置为false
        // 若设置为true则数据库将会把每一次数据更新认定为一个事务并自动提交
        conn.setAutoCommit(false);
        stmt = conn.createStatement();
        // 将 “张三” 账户中的金额减少100
        stmt.execute("UPDATE account SET money = money - 100 WHERE name = '张三'");

        //TODO 发生了异常
        //int a = 1/0;
        
        // 将 “李四” 账户中的金额增加100
        stmt.execute("UPDATE account SET money = money + 100 WHERE name = '李四'");
        // 提交事务
        conn.commit();
        // 事务提交：转账的两步操作同时成功
    } catch (Exception sqle) {
        try {
            // 发生异常，回滚在本事务中的操做
            // 事务回滚：转账的两步操作完全撤销
            conn.rollback();
        } catch (Exception ignore) {
        }
        sqle.printStackTrace();
    } finally {
        stmt.close();
        conn.close();
    }
}

//JDBCConnectionUtil
public static Connection getConnection() throws SQLException {
    String url = "jdbc:mysql://localhost:3306/tx?serverTimezone=UTC&characterEncoding=utf-8";
    String user = "root";
    String password = "123456";
    String className = "com.mysql.cj.jdbc.Driver";
    try {
        Class.forName(className);
    } catch (ClassNotFoundException e) {
        log.error(e.getMessage());
    }
    return DriverManager.getConnection(url, user, password);
}