NHibernate Step by Step(二) 单表操作
接着第一期,我们继续。
为了方便学习测试,从今天开始我将使用MS Test来进行测试,这样就避免了在一个Console工程里不停地添加、注释代码了。
提示:为了在VS2005IDE中获得NHibernate配置文件的代码提示,请将你的$NHibernate/src/NHibernate下的nhibernate-configuration-2.0.xsd、nhibernate-mapping-2.0.xsd拷贝到/Program Files/Microsoft Visual Studio 8/Xml/Schemas下,这样当你编辑配置文件或者映射文件时,你将得到完整的代码提示。
VS2003请拷贝到/Program Files/Microsoft Visual Studio .NET 2003/Common7/Packages/schemas/xml下。
NHibernat内部使用log4net来进行日志操作,今天我们将在配置文件中添加log4net的配置,这样我们在测试的时候将可以清楚地看到NHibernate是如何进行工作的。
应用配置文件修改如下:
请注意添加:
关于log4net的使用,我们这里不做详细的讲解,有兴趣的请参考如下地址:
http://logging.apache.org/log4net/
接着,我们在上次的工程组中添加一个名为Test1的测试项目,将其中的不需要的手动测试去掉。请注意:除了NHibernate/Model引用外,还需要添加如下3个引用:
log4net,System.Data,System.Xml.
修改代码如下:
我们在测试的开始对Configuration/SessionFactory/Log进行初始化。在每一个Test的开始获取一个新的session,每一个Test结束后即关闭session。
添加如下一个Get测试:
我们在前面曾经插入一条名为“Jackie Chan”的记录,现在在Test Manager中选中TestRead,运行,ok,Passed!
我们使用了session.Get来获取记录,方法如下:
objectGet(Typeclazz,objectid);
很简单,一目了然。
我们切换到Test Results窗口,双击测试成功的TestRead方法,这时将会有一个详细的测试结果显示出来,NHibernate将使用我们指定的log4net来输出详细信息,我们仔细观察:
2006-04-15 13:52:13,000 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - opened session
2006-04-15 13:52:13,015 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - loading [Person#1]
2006-04-15 13:52:13,015 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - attempting to resolve [Person#1]
2006-04-15 13:52:13,015 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - object not resolved in any cache [Test.Model.Person#1]
2006-04-15 13:52:13,015 [AdpaterExeMgrThread1] DEBUG NHibernate.Persister.EntityPersister [(null)] - Materializing entity: Test.Model.Person#1
2006-04-15 13:52:13,078 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.BatcherImpl [(null)] - Opened new IDbCommand, open IDbCommands :1
2006-04-15 13:52:13,078 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.BatcherImpl [(null)] - Building an IDbCommand object for the SqlString: SELECT person0_.id as id0_, person0_.name as name0_ FROM Person person0_ WHERE person0_.id=:id
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.Type.Int32Type [(null)] - binding '1' to parameter: 0
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] INFO NHibernate.Loader.Loader [(null)] - SELECT person0_.id as id0_, person0_.name as name0_ FROM Person person0_ WHERE person0_.id=@p0
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.SQL [(null)] - SELECT person0_.id as id0_, person0_.name as name0_ FROM Person person0_ WHERE person0_.id=@p0
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.SQL [(null)] - @p0 = '1'
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.Connection.DriverConnectionProvider [(null)] - Obtaining IDbConnection from Driver
2006-04-15 13:52:13,859 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.BatcherImpl [(null)] - Opened Reader, open Readers :1
2006-04-15 13:52:13,859 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - processing result set
2006-04-15 13:52:13,875 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - result row: 1
2006-04-15 13:52:13,875 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - Initializing object from DataReader: 1
2006-04-15 13:52:13,875 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - Hydrating entity: Test.Model.Person#1
2006-04-15 13:52:13,906 [AdpaterExeMgrThread1] DEBUG NHibernate.Type.StringType [(null)] - returning 'Jackie Chan' as column: name0_
2006-04-15 13:52:13,906 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - done processing result set (1 rows)
2006-04-15 13:52:13,937 [AdpaterExeMgrThread1] DEBUG NHibernate.Driver.NHybridDataReader [(null)] - running NHybridDataReader.Dispose()
2006-04-15 13:52:13,937 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.BatcherImpl [(null)] - Closed Reader, open Readers :0
2006-04-15 13:52:13,937 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.BatcherImpl [(null)] - Closed IDbCommand, open IDbCommands :0
2006-04-15 13:52:13,937 [AdpaterExeMgrThread1] DEBUG NHibernate.Loader.Loader [(null)] - total objects hydrated: 1
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - resolving associations for: [Test.Model.Person#1]
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - done materializing entity [Test.Model.Person#1]
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - initializing non-lazy collections
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - closing session
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - disconnecting session
2006-04-15 13:52:13,953 [AdpaterExeMgrThread1] DEBUG NHibernate.Connection.ConnectionProvider [(null)] - Closing connection
2006-04-15 13:52:13,968 [AdpaterExeMgrThread1] DEBUG NHibernate.Impl.SessionImpl [(null)] - transaction completion
在其中,我们可以发现:
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.SQL [(null)] - SELECT person0_.id as id0_, person0_.name as name0_ FROM Person person0_ WHERE person0_.id=@p0
2006-04-15 13:52:13,093 [AdpaterExeMgrThread1] DEBUG NHibernate.SQL [(null)] - @p0 = '1'
对了,就是这里,NHibernate替我们构造了一条sql语句,并添加一个参数,然后将我们在代码中赋的id值1来填充,这样,一条完整的可以执行的sql语句产生了。
请注意:在产生sql语句的前面,NHibernate构造了一个IDBCommand,然后在sql语句产生完全后,获取连接,通过一个DataReader来填充Persion对象给我们使用,这就是NHibernate替我们做的事,是不是很简单啊?(真的很简单吗??看看源代码吧!!)
请仔细研究输出的日志。
如法炮制,我们添加另外3个Test,完成单个表的全部CRUD操作,如下完整代码:
Delete的方法如下:
直接传入需要delete的对象即可。
好了,基本的操作都完成了,是不是很Easy?
好了,这一篇就讲这么多,我们下次再接着练习。
Step by Step,顾名思义,是一步一步来的意思,整个教程我将贯彻这一理念。
任何建议或者批评,请e:[email protected]