Dynamically loading the values for property placeholders in context xml file

[al_zawia]

Hi,

I am running some JUnit tests cases, and I trying to dynamically load the values for certain property placeholder in my context xml file during runtime.

For example, I have a JUnit class that has 5 different test cases (i.e. 5 test methods in one Test class); all of these test cases share the same context xml file, such as the one below:

  <bean id="resolver" class="org.springframework.xml.castor.CastorResolverFactoryBean">
    <property name="mappingLocations">
      <list>
        <value>${folder.path}/castor-mapping.xml</value>
      </list>
    </property>
  </bean>
  
  <bean id="unmarshaller" class="org.springframework.xml.castor.CastorUnmarshallerFactoryBean">
    <property name="resolver" ref="resolver"/>
  </bean>

I have the JUnit Test class which contains the following setup method:

    protected void setUp() throws Exception
    {
        /*
         * Load the unmarshaller object through Spring FactoryBean
         */
        ApplicationContextUtil appContextUtil = new ApplicationContextUtil();
        unmarshaller = (Unmarshaller) appContextUtil.getBean("unmarshaller");
    }

And in my JUnit I have 5 test methods, for example, testMethod1(), testMethod2(), ...etc. And each test method has its own testdata subfolder path, for example, folder paths: testdata/testMethod1, testdata/testMethod2, ....etc.

Each testdata subfolder contains a different version of castor-mapping.xml file, which is purposely made different for each test method for testing purposes. So there are a total of 5 testdata subfolders, with 5 different castor-mapping.xml files. And basically for each test case I want to be able to dynamically replace the ${folder.path} property placeholder with the correct testdata folder path for that JUnit test method. This way the unmarshaller bean would get loaded from the Spring factory bean with the correct castor-mapping.xml file for the JUnit test method that is being executed.

How can I set the value of the ${folder.path} property in the context xml file during runtime for each one of my test methods? I already thought about using the PropertyPlaceholderConfigurer, but that wouldn't work, because the ${folder.path} property would get set to the same value in the context xml file for all the test methods within my JUnit.

Any help is very much appreciated.

Thanks.

[karldmoore]

I'm not sure if there is a nice way to sort this out. The PropertyPlaceholderConfigurer will run and replace anyvalues as required. What you want to do is re-run this later once changing the replacement. I don't think this is possible as once it's been substituted that's it. I guess you could manually set the value within each test by calling the setter.

[al_zawia]

Yes, I agree. I don't think there is a clean way for doing this with Spring. For now I was able to handle this situation by the doing the following extra code.

// Attempt to load resource from class path
Resource resource = new ClassPathResource(contextLocation);

// instantiate factory bean with resource
XmlBeanFactory xmlBeanFactory = new XmlBeanFactory(resource);

PropertyPlaceholderConfigurer cfg = new PropertyPlaceholderConfigurer();
cfg.setProperties(props);

// now actually do the replacement (replace property place holders
// in the context xml file with values from the properties object)
cfg.postProcessBeanFactory(xmlBeanFactory);

In the above code the contextLocation variable holds the file path for the spring context xml file, and the props is a java.util.Properties object that holds the properties that need to be replaced in the spring context xml file. I have thought about using the ApplicationContext rather than the BeanFactory, but I was not able to achieve the above with ApplicationContext's implementations. So I resorted to using the XmlBeanFactory for solving this problem.

[karldmoore]

I've not used it yet, but the parameterized test feature of JUnit4 might have been useful here. I'm not sure it's entirely what you were trying to do.
http://www.devx.com/Java/Article/31983/1954?pf=true