java事务 - 传递Connection

package com.zdp.service; import java.sql.Connection; import java.sql.SQLException; import com.zdp.dao.AccountDAO; import com.zdp.domain.Account; import com.zdp.utils.JDBCUtils; /** * 业务逻辑层 */ public class AccountService { public void transfer(Account outAccount, Account inAccount, int money) throws SQLException { // 开启 事务 Connection conn = JDBCUtils.getConnection(); conn.setAutoCommit(false); // 查询两个账户 AccountDAO accountDAO = new AccountDAO(); outAccount = accountDAO.findAccountById(outAccount.getId()); inAccount = accountDAO.findAccountById(inAccount.getId()); // 转账 - 修改原账户金额 outAccount.setMoney(outAccount.getMoney() - money); inAccount.setMoney(inAccount.getMoney() + money); try { // 更新账户金额, 注意: 这里往Dao层传递连接 accountDAO.update(outAccount, conn); // int x = 1 / 0; accountDAO.update(inAccount, conn); // 转账成功, 提交事务 conn.commit(); } catch (Exception e) { // 转账失败, 回滚事务 conn.rollback(); e.printStackTrace(); } } }