title: Creating a constructor in a test case so that it will only be called once
body: <p>Trying to create a constructor that is only called once in my unit tests</p>
  
  <pre><code>public class ArtistTest extends InstrumentationTestCase{
      private static final String TAG_NAME = "TESTING_SUITE";
      private TestingMusicDAO musicDAO;
      private List&lt;Song&gt; songs;
      private Instrumentation instr;
      MusicService musicService;
  
      public ArtistTest() throws Exception {
          super();       
          instr = this.getInstrumentation();
          Log.d(TAG_NAME, "Setting up testing songs");
          musicDAO = new TestingMusicDAO(instr.getContext());
          musicService = new MusicServiceImpl(musicDAO);
          musicDAO.getAllSongsFromFile();
          songs = musicDAO.getAllSongs();
          for(Song song : songs)
              Log.d( TAG_NAME, song.toString() );
      }
  </code></pre>
  
  <p>But I get an Exception in constructor error when I run the file as a Android Junit Test. Also here is the stack trace</p>
  
  <pre><code> junit.framework.AssertionFailedError: Exception in constructor: test0      (java.lang.NullPointerException
   at com.intellimec.ilane.ice.mediaservices.ArtistTest.&lt;init&gt;(ArtistTest.java:17)
   at java.lang.reflect.Constructor.constructNative(Native Method)
   at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
   at junit.runner.BaseTestRunner.getTest(BaseTestRunner.java:118)
   at android.test.AndroidTestRunner.getTest(AndroidTestRunner.java:148)
   at android.test.AndroidTestRunner.setTestClassName(AndroidTestRunner.java:56)
   at   android.test.suitebuilder.TestSuiteBuilder.addTestClassByName(TestSuiteBuilder.java:80)
   at android.test.InstrumentationTestRunner.parseTestClass(InstrumentationTestRunner.java:444)
   at android.test.InstrumentationTestRunner.parseTestClasses(InstrumentationTestRunner.java:425)
   at android.test.InstrumentationTestRunner.onCreate(InstrumentationTestRunner.java:370) 
   at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4382)
   at android.app.ActivityThread.access$1300(ActivityThread.java:141)
   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1294)
   at android.os.Handler.dispatchMessage(Handler.java:99)
   at android.os.Looper.loop(Looper.java:137)
   at android.app.ActivityThread.main(ActivityThread.java:5039)
   at java.lang.reflect.Method.invokeNative(Native Method)
   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
   at dalvik.system.NativeStart.main(Native Method)
   )
   at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:190)
   at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:175)
   at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:555)
   at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1661)
  </code></pre>