1、开启事务（关闭自动提交则默认开启事务）

conn.setAutoCommit(false);

2、一组业务执行完毕，提交事务

conn.commit();

3、可以在catch语句中显示的定义回滚语句，但默认失败就会回滚

conn.rollback();

示例：

package com.test.third;

import com.test.second.JdbcUtils;

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

public class TransactionTest {

    public static void main(String[] args) {

        Connection conn = null;
        PreparedStatement st = null;
        ResultSet rs = null;

        try {
            conn = JdbcUtils.getConnection();
            // 关闭自动提交（开启事务）
            conn.setAutoCommit(false);

            String sql1 = "update `account` set money = money - ? where `id` = ?";
            st = conn.prepareStatement(sql1);
            st.setInt(1,100);
            st.setInt(2,1);
            st.executeUpdate();

            String sql2 = "update `account` set money = money + ? where `id` = ?";
            st = conn.prepareStatement(sql2);
            st.setInt(1,100);
            st.setInt(2,2);
            st.executeUpdate();

            // 提交事务
            conn.commit();
            System.out.println("构建成功");
        } catch (SQLException e) {
            try {
                // 失败则回滚
                conn.rollback();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
            e.printStackTrace();
        } finally {
            JdbcUtils.release(conn,st,rs);
        }
    }
}

Q.E.D.