struts2与jpa(hibernate实现)整合使用过程中碰到的一个匪夷所思的问题.

1.首先简要介绍一下出现的问题的环境
jdk1.6+strut2.0.11.1+Spring2.5+hibernate3.2.6.ga
使用了SpringOpenEntityManagerInViewFilter作为lazyloading.
2.问题出现的步骤和相关代码
主要问题:在action的某个方法中执行完添加数据的操作(insert)后返回success后跳转到添加页面后莫名其妙的又执行了一个update操作,把我插入数据库的数据给修改了.
代码如下
进入添加页面前的action方法

	public String contractorsaSignup() throws Exception
	{
		if (apparelhrContractor == null) {
			apparelhrContractor = new ApparelhrContractor();
			apparelhrContractor.setContractorTitle("test");
			apparelhrContractor.setContractorDescription("test");
			apparelhrContractor.setRegistrationDate(Globals.getCurrentSqlDate());
			apparelhrContractor.setPostDate(apparelhrContractor.getRegistrationDate());
		}
		return SUCCESS;		
	}

插入数据库数据的action方法

	public String contractorsaCreate() throws Exception {
		if (apparelhrContractor != null) {
			apparelhrContractor.setContractorTitle("");
			apparelhrContractor.setContractorDescription("");
			apparelhrContractorService.addApparelhrContractor(apparelhrContractor);
			String resultMessage = getText("contractorsa.success");
			addActionMessage(resultMessage);
		}
		return SUCCESS;
	}

struts.xml配置

		<action name="*Front" class="contractorAction" method="{1}" >
			<result>/contractorsaSignup.jsp</result>
		</action>

以上两个action方法都跳转到同一个页面contractorsaSignup.jsp
我的本意是想把页面提交上来数据中的ContractorTitle和ContractorDescription字段人为清空.
结果执行完insert操作跳转到contractorsaSignup.jsp页面后又把已经清空额ContractorTitle,ContractorDescription数据给update回去了.
后台的log输出如下

Hibernate: insert into apparelhr_contractor (city, company_brief, company_name, contact_persion, contractor_description, contractor_title, country, email, mobile, post_date, registration_date, service_offered, street, suburb, telephone) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
2008-5-9 11:12:49 com.opensymphony.xwork2.interceptor.TimerInterceptor doLog
信息: Executed action [/include/contractorSubMenu!execute] took 16 ms.
2008-5-9 11:12:49 com.opensymphony.xwork2.interceptor.TimerInterceptor doLog
信息: Executed action [//contractorsaCreateFront!contractorsaCreate] took 828 ms.
Hibernate: select apparelhrl0_.link_id as link1_6_, apparelhrl0_.content as content6_, apparelhrl0_.create_date as create3_6_, apparelhrl0_.sequence as sequence6_, apparelhrl0_.title as title6_, apparelhrl0_.url as url6_ from apparelhr_link apparelhrl0_ order by apparelhrl0_.sequence
Hibernate: update apparelhr_contractor set city=?, company_brief=?, company_name=?, contact_persion=?, contractor_description=?, contractor_title=?, country=?, email=?, mobile=?, post_date=?, registration_date=?, service_offered=?, street=?, suburb=?, telephone=? where contractor_id=?

大家可以看到执行完insert回到contractorsaSignup.jsp后又执行了个update语句.
但是如果我把

apparelhrContractor.setContractorTitle("");
apparelhrContractor.setContractorDescription("");

给去掉就不会又update语句出现了.
实在是不知道为什么会出现这种奇怪现象,还请兄弟们给指点指点.

找到原因了.
原来是
select apparelhrl0_.link_id as link1_6_, apparelhrl0_.content as content6_, apparelhrl0_.create_date as create3_6_, apparelhrl0_.sequence as sequence6_, apparelhrl0_.title as title6_, apparelhrl0_.url as url6_ from apparelhr_link apparelhrl0_ order by apparelhrl0_.sequence
这个sql查询在作怪.
由于原来的jpa事务没有把数据库检索的事务设置成readonly导致在查询的以上数据的时候启用了事务处理,hibernate执行了接下来得update操作.

但是一个搞不懂的地方就是,就算我查询用了事务,但是我在插入数据库数据前就已经
执行了如下代码

apparelhrContractor.setContractorTitle("");   
apparelhrContractor.setContractorDescription("");  

为何hibernate还要把我已经插入数据库得数据给update回页面提交上来的原始数据.

真的很费解啊.