java事务 - threadlocal

package com.zdp.dao; import java.sql.Connection; import java.sql.SQLException; import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.BeanHandler; import com.zdp.domain.Account; import com.zdp.utils.JDBCUtils; import com.zdp.utils.TransactionManager; /** * DAO层: CRUD */ public class AccountDAO { // 查询账户 public Account findAccountById(int id) throws SQLException { String sql = "select * from account where id = ?"; Object[] params = {id}; QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDataSource()); return queryRunner.query(sql, new BeanHandler<Account>(Account.class), params); } // 更新账户 public void update(Account account) throws SQLException { String sql = "update account set name = ?, money = ? where id = ?"; Object[] params = {account.getName(), account.getMoney(), account.getId()}; // 从threadLocal中获取连接, 同一个线程拿到的是同一个连接 Connection conn = TransactionManager.getConnection(); QueryRunner queryRunner = new QueryRunner(); queryRunner.update(conn, sql, params); } }