jdbc设置手动提交事务后还有必要考虑回滚吗？

Question

jdbc设置手动提交事务后还有必要考虑回滚吗？只要执行不到commit()方法之前就算有异常那也不会提交事务啊，对数据也没有影响啊。

18行到39行

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

public class Test {
    public static void main(String[] args) {
        Connection connection = null;
        PreparedStatement preparedstatement = null;
        try {
            //1.注册驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            //2.获取连接
            String url = "jdbc:mysql:/";
            String username = "";
            String password = "";
            connection = DriverManager.getConnection(url,username,password);
            connection.setAutoCommit(false);//手动提交
            //3.获取数据库操作对象
            preparedstatement = connection.prepareStatement("update account set balance = ? where id = ?");
            //传值
            preparedstatement.setInt(1,5000);
            preparedstatement.setString(2,"zhang");
            //4.执行sql
            preparedstatement.executeUpdate();

            String s = null;//模拟中途出现异常，后面语句无法执行
            s.toString();
            //传值
            preparedstatement.setInt(1,5000);
            preparedstatement.setString(2,"li");
            //4.执行sql
            preparedstatement.executeUpdate();
            connection.commit();//手动提交
        } catch (Exception throwables) {
            //捕获到异常回滚事务
            if (connection != null) {
                try {
                    connection.rollback();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            throwables.printStackTrace();
        }finally {
            //6.释放资源
            if (preparedstatement != null) {
                try {
                    preparedstatement.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (connection != null) {
                try {
                    connection.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
        }
    }
}

Answer 1

你的理解是对的。在异常捕获中处理回滚即可。没有执行到commit方法不会提交数据的。望采纳！！