Struts2; keeping a session open for StrutsSpringTestCase JUnit tests - spring

Question

My project architecture is Struts2 with Spring integration and JPA/Hibernate. StrutsSpringTestCase base class is utilized for JUnit integration tests.
Under normal circumstances, the following configuration in web.xml keeps a single session open from start to finish of each request:
<filter>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
As a result, all lazy loading works fine in all services. For example:
#Override
public Person find(int id) {
Person person = personDao.find(id);
// Take care of lazy loading before detaching the object for
// the view layer...
person.getGender().getCode();
// Detach the object so that it can be used for data transfer
// (as a DTO) without causing JPA issues and errors...
getEntityManager().detach(person);
return person;
}
Now... issues arise when I try to run the integration tests, which are independent of the OpenEntityManagerInViewFilter configuration in web.xml.
What happens is that since there is no session being kept open from start to finish of each request, lazy loading statements like "person.getGender().getCode()" don't work any longer, and I get the "could not initialize proxy - no Session" errors.
One solution I'm aware of is to force the #Transactional annotation upon the service methods that are having the lazy-loading issues, which will result in a session being open from start to finish of the method call. I tested it and it fixed the problem:
#Transactional
#Override
public Person find(int id) {
Person person = personDao.find(id);
// Take care of lazy loading before detaching the object for
// the view layer...
person.getGender().getCode();
// Detach the object so that it can be used for data transfer
// (as a DTO) without causing JPA issues and errors...
getEntityManager().detach(person);
return person;
}
However, this could be overkill as the method doesn't need a transaction under normal circumstances. I'm wondering if there is another solution that doesn't require to compromise on the service side.
Is there something I can add to my test classes (which extend StrutsSpringTestCase) to keep the session open? Or is there perhaps an elegant configuration solution on the Spring or JUnit side?
Here is my Spring configuration file - applicationContext.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd"
default-dependency-check="all"
default-lazy-init="false"
default-autowire="byName">
<!-- *************** MAIN CONFIGURATION SECTION *************** -->
<!-- Bean post-processor for JPA annotations. -->
<!-- Make the Spring container act as a JPA container and inject an EnitityManager from
the EntityManagerFactory. -->
<bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"
autowire="no"
dependency-check="none" />
<!-- ** Data Source Configuration ** -->
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close"
autowire="no"
dependency-check="none">
<!-- Database configuration: -->
<property name="driverClass" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://localhost/**********" />
<property name="user" value="**********" />
<property name="password" value="**********" />
<!-- C3P0 pooling properties configuration: -->
<property name="acquireIncrement" value="4" />
<property name="initialPoolSize" value="4" />
<property name="minPoolSize" value="4" />
<property name="maxPoolSize" value="20" />
<property name="maxIdleTime" value="600" />
<property name="maxConnectionAge" value="1800" />
</bean>
<!-- ** JPA Vendor Selection ** -->
<bean id="jpaVendorAdapter"
class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"
autowire="no"
dependency-check="none" />
<!-- ** JPA Vendor and Entity Manager Configuration ** -->
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
autowire="no"
dependency-check="none">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter" ref="jpaVendorAdapter" />
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
<!-- Have the JPA vendor manage the database schema: -->
<prop key="hibernate.hbm2ddl.auto">create</prop>
<prop key="hibernate.cache.use_second_level_cache">true</prop>
<prop key="hibernate.cache.use_query_cache">true</prop>
<prop key="hibernate.cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</prop>
<prop key="hibernate.max_fetch_depth">4</prop>
<prop key="hibernate.jdbc.batch_size">1000</prop>
<prop key="hibernate.show_sql">false</prop>
<prop key="hibernate.format_sql">false</prop>
</props>
</property>
</bean>
<!-- ** Transaction Manager Configuration ** -->
<bean id="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager"
autowire="no"
dependency-check="none">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<!-- ** Transaction Annotation Configuration; classes/functions with #Transactional will
get a framework transaction. ** -->
<tx:annotation-driven transaction-manager="transactionManager" />
<!-- **** DETAILED SERVICE BEAN CONFIGURATION WAS TAKEN OUT TO SHORTEN THE FILE **** -->
</beans>
I would appreciate any pointers.
EDIT:
To make things a bit more visual, the following test generates an exception when the service method in question encounters lazy loading and the service method is not annotated with #Transactional, but works just fine when the service method is annotated with #Transactional.
public class ActionTest extends CustomActionTestBase {
public ActionTest() {
super("/web/someAction"); // the action to test
}
#Override
public void testHelperActionLoggedIn() throws Exception {
procApplyContinualSessionForAdmin(); // the numerous steps to get logged in
procExecuteAction(
helpGetPrimaryActionURI(), // use the action URI set by the constructor above
helpPrepareActionParams( ) // no parameters are passed to this action
);
procConfirmOutcome(ActionSupport.SUCCESS,0,0,0,false);
}
}
Note: CustomActionTestBase extends StrutsSpringTestCase (which in turn extends some JUnit stuff). I needed CustomActionTestBase due to some heavy test case customization/automation.
EDIT:
I also tried adding #Transactional to the "testHelperActionLoggedIn()" test method itself, which didn't change the outcome.
EDIT:
Additionally, I tried to make things more Spring-specific (as instructed by Aleksandr M) by annotating with #RunWith, #ContextConfiguration, and #Test.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations={"classpath:applicationContext.xml"})
public class ActionTest extends CustomActionTestBase {
public ActionTest() {
super("/web/someAction"); // the action to test
}
#Test
#Override
public void testHelperActionLoggedIn() throws Exception {
procApplyContinualSessionForAdmin(); // the numerous steps to get logged in
procExecuteAction(
helpGetPrimaryActionURI(), // use the action URI set by the constructor above
helpPrepareActionParams( ) // no parameters are passed to this action
);
procConfirmOutcome(ActionSupport.SUCCESS,0,0,0,false);
}
}
It resulted in an exception that showed up in the JUnit Failure Trace - there was no exception output in the console for whatever reason.
Exception details:
java.lang.NullPointerException
at org.apache.struts2.StrutsTestCase.getActionMapping(StrutsTestCase.java:196)
at org.apache.struts2.StrutsTestCase.getActionMapping(StrutsTestCase.java:206)
at com.mycompany.utils.test.CustomActionTestBase.examineActionMapping(CustomActionTestBase.java:402)
at com.mycompany.utils.test.CustomActionTestBase.procExecuteAction(CustomActionTestBase.java:158)
at com.mycompany.utils.test.CustomActionTestBase.execLoginActionForAdmin(CustomActionTestBase.java:505)
at com.mycompany.utils.test.CustomActionTestBase.procApplyContinualSessionForAdmin(CustomActionTestBase.java:106)
at com.mycompany.actions.web.ActionTest.testHelperActionLoggedIn(ActionTest.java:30)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:82)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:240)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:180)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
It looks like it's having trouble with getting the action mapping, which it didn't before.

Answer 1

You can put #Transactional annotation over test method and you need to run your tests with spring in order it could find #Transactional annotation. To use JUnit4 in Struts2 tests you need to extend StrutsSpringJUnit4TestCase. So your test class should look something like that:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations={"classpath:applicationContext.xml"})
public class ActionTest extends StrutsSpringJUnit4TestCase {
#Transactional
#Test
public void testHelperActionLoggedIn() throws Exception {
// ...
}
}
Note: If you need to obtain ActionProxy you can get it by calling getActionProxy method. You probably need to create new session map for it and then you can call execute.
ActionProxy actionProxy = getActionProxy("/action");
Map<String, Object> sessionMap = new HashMap<String, Object>();
actionProxy.getInvocation().getInvocationContext().setSession(sessionMap);
actionProxy.execute();
BUT if you don't need reference to ActionProxy then you can use executeAction method to execute action in this way you don't need to create new session map.
executeAction("/action");