JDBC事务回滚

import com.atguigu1.util.JDBCUtils;
import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.junit.Test;
import java.sql.Connection;
import java.sql.SQLException;

public class exe {
    @Test
    public void exe() {

        Connection conn = null;
        try {
            // 1.获取数据库连接
            conn = JDBCUtils.getConnection3();
            // 2.开启事务
            conn.setAutoCommit(false);
            // 3.进行数据库操作
            QueryRunner runner=new QueryRunner();
            String sql1 = "update user_table set balance = balance - 100 where user = ?";
            runner.update(conn, sql1, "AA");

            // 模拟网络异常
            //System.out.println(10 / 0);

            String sql2 = "update user_table set balance = balance + 100 where user = ?";
            runner.update(conn, sql2, "BB");
            // 4.若没有异常，则提交事务
            conn.commit();
        } catch (Exception e) {
            e.printStackTrace();
            // 5.若有异常，则回滚事务
            try {
                conn.rollback();
            } catch (SQLException e1) {
                e1.printStackTrace();
            }
        } finally {
            try {
                //6.恢复每次DML操作的自动提交功能
                conn.setAutoCommit(true);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            //7.关闭连接
            DbUtils.closeQuietly(conn);
        }
    }
}