Java练习笔记 -ThreadLocal的一种应用场景

用ThreadLocal来存储数据库连接

代码如下

public class DataSourceUtils {

private static DataSource dataSource = new ComboPooledDataSource();

private static ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

public static DataSource getDataSource() {
return dataSource;
}

/**
* 当DBUtils需要手动控制事务时，调用该方法获得一个连接
* 
* @return
* @throws SQLException
*/
public static Connection getConnection() throws SQLException {

Connection con = tl.get();

if (con == null) {
con = dataSource.getConnection();
tl.set(con);
}

return con;
}

// 开启事务
public static void startTransaction() throws SQLException {

getConnection().setAutoCommit(false); //设置事务为手动事务，相当于开启事务

}

// 事务回滚
public static void rollback() throws SQLException {
getConnection().rollback();
}

// 事务提交
public static void commitAndReleased() throws SQLException {

getConnection().commit(); // 事务提交
getConnection().close();// 释放connection，是将其放回到连接池.
tl.remove();
}

}