Not looking so much for a fix as what this error means

[Tony Evans]

I notice that many posters post,a n ask for a fix without asking what the error means.

When I start up JBoss I get the following error

rg.springframework.beans.TypeMismatchException: 
Failed to convert property value of type [com.arjuna.ats.jbossatx.jta.TransactionManagerDelegate] 
to required type [javax.transaction.TransactionManager] for property 'jtaTransactionManager'; 
nested exception is java.lang.IllegalArgumentException: No matching editors or conversion strategy found

I am more interested with understanding what the error is.

As I understand it we have a JBoss object com.arjuna.ats.jbossatx.jta.TransactionManagerDelegate

which needs to be converted or matched to a javax.transaction.TransactionManager

for the spring object jtaTransactionManager.

I am not sure what "No matching editors or conversion strategy found"

Since I am upgrading an application from jboss 4 to jboss 5 I would guess that the current jar containing javax.transaction.TransactionManager does not work with JBoss 5 and I need to get a later version.

I am more interested in understanding the error than just getting a fix. This is also a laerning exercise.

Thanks

[Tony Evans]

com.arjuna.ats.jbossatx.jta.TransactionManagerDelegate is contained in the
jbossjts-integration.jar which comes with jboss-5.1.0.GA.

So it looks that jtaTransactionManager org.springframework.jndi.JndiObjectFactoryBean needs to be updated

[Tony Evans]

TransactionManagerDelegate extends BaseTransactionManagerDelegate which implements TransactionManager.

Therefore I do not understand the error as its casting an object that implements the interface TransactionManager to TransactionManager. That is if I understand the error correctly.

Will welcome any input even a good guesstimate. Most fixes have come through discussion which helps you to understand the problem more.

[Mark Spritzler]

To me the error simply is stating that it is trying to cast one type to the other and they aren't compatible. One is a class from JBoss and one is a class from Spring. They shouldn't be in the same hierarchy. Whenever you are using JTA in a Spring applictation, the Spring TransactionManager class for that server is really just delegating calls to the JTA Transaction manager class in JBoss, in this case.

We need a bit more context to state why you are getting this error. But the meaning is as simple as


public class Mark {}

Mark mark = new Mark()

someReferenceToSomeOtherClass.setJohn(mark);

where setJohn's signature is setJohn(John john);

Since this is in configuration, Spring tries to convert the Mark into a John, but Mark isn't a John. And Spring catches the ClassCastException here and throws their Conversion/Editor error. Remember Spring xml configuration is all Strings and Spring uses PropertyEditors or Converters to set things up.

Mark

[Tony Evans]

Thanks Mark I understand the error now.

I am converting a app to run on jboss-5.1.0.GA from jboss-4.0.5.GA.

In one of my applicatioContext.xml I ahave the following

 <!-- Get the javax.transaction.TransactionManager for hibernate -->
    <bean id="jtaTransactionManager"
        class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName">
            <value>java:/TransactionManager</value>
        </property>
    </bean>

which returns the object com.arjuna.ats.jbossatx.jta.TransactionManagerDelegate which as you pointed out it trys to cast to javax.transaction.TransactionManager

TransactionManagerDelegate extends BaseTransactionManagerDelegate
BaseTransactionManagerDelegate implements javax.transaction.TransactionManager.

So the cast should be allowed, that is now the confusing bit.

[Mark Spritzler]

Tony Evans wrote:Thanks Mark I understand the error now.

I am converting a app to run on jboss-5.1.0.GA from jboss-4.0.5.GA.

In one of my applicatioContext.xml I ahave the following

 <!-- Get the javax.transaction.TransactionManager for hibernate -->
    <bean id="jtaTransactionManager"
        class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName">
            <value>java:/TransactionManager</value>
        </property>
    </bean>

Why aren't you just using

<tx:jta-transaction-manager/> tag

This will create a TransactionManager for you using whatever app server you are deployed in. It automatically figures it out and delegates to the app servers JTA Transaction Manager.

Mark

[Tony Evans]

Thanks Mark, as it stands I am stripping my application down, I dont think it needs TransactionManager, the app is now wrapped in another app an just needs to supply web pages that are iframed.

Found out that JBoss 5 is a lot stricter on parsing XML than JBoss 4 was.

If I do need the TransactionManager, I will use your suggestion.

[Mark Spritzler]

Tony Evans wrote:Thanks Mark, as it stands I am stripping my application down, I dont think it needs TransactionManager, the app is now wrapped in another app an just needs to supply web pages that are iframed.

Found out that JBoss 5 is a lot stricter on parsing XML than JBoss 4 was.

If I do need the TransactionManager, I will use your suggestion.

I'm not sure I understand why you won't need a TransactionManager. If anyone is calling into that app and inside that app you have use cases and you access the database, you need a TransactionManager.

Mark