JUnit.org Resources for Test Driven Development

Hi I've been suffering a NUll Pointer exception when i try to run my java file as a test case ,, the input is an xml file.. any suggestions on this is appreciable... I've pasted the stack trace...

java.lang.NullPointerException
at java.io.FileInputStream.(Unknown Source)
at org.junitext.runners.parameters.factory.DigesterParameterFactory.createParameters(Unknown Source)
at org.junitext.runners.XMLParameterizedRunner$RunAllXMLParameterMethods.getParametersList(Unknown Source)
at org.junitext.runners.XMLParameterizedRunner$RunAllXMLParameterMethods.(Unknown Source)
at org.junitext.runners.XMLParameterizedRunner.(Unknown Source)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:23)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.(JUnit4TestReference.java:26)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.(JUnit4TestClassReference.java:24)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:34)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:24)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:445)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)