title: Getting a runtime Exception with parameterized Junit test
body: <pre><code>@RunWith(value=Parameterized.class)
  public class TestHashMapParams {
  
      HashMap dataToTest;
      String cont;
      public void TestHashMapParams(HashMap dataToTest)
      {
          this.dataToTest=cont;
      }
  
  
      @Test
      public void hashTest()
      {
          System.out.println(dataToTest.get("Key"));
      }
  
  
      @Parameters
      public static Collection giveMe()
      {
          ArrayList&lt;HashMap[]&gt; ab=new ArrayList&lt;HashMap[]&gt;();
          HashMap[] bc1=new HashMap[1];
          HashMap[] bc2=new HashMap[1];
  
          HashMap a1=new HashMap&lt;&gt;();
          HashMap a2=new HashMap&lt;&gt;();
  
          //HashMap arr[] = {new HashMap(), new HashMap()};
          ArrayList&lt;HashMap&gt; itrtor1=new ArrayList&lt;HashMap&gt;();
          ArrayList&lt;HashMap&gt; itrtor2=new ArrayList&lt;HashMap&gt;();
  
          a1.put("Key", "val1");
          a2.put("Key","val2");
  
          itrtor1.add(a1);
          itrtor2.add(a2);
  
          bc1=itrtor1.toArray(new HashMap[itrtor1.size()]);
          bc2=itrtor2.toArray(new HashMap[itrtor2.size()]);
  
          ab.add(bc1);
          ab.add(bc2);
  
          return ab;
      }
  }
  
  
  
  java.lang.IllegalArgumentException: wrong number of arguments
      at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
  </code></pre>
  
  <p>The above parameterized test meant to run two times giving a Runtime exception!! Though it runs two times but the above exception appears</p>
  
  <p>What might be going wrong here??</p>
  
  <p>Full stack trace</p>
  
  <pre><code>java.lang.IllegalArgumentException: wrong number of arguments
      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.runners.Parameterized$TestClassRunnerForParameters.createTestUsingConstructorInjection(Parameterized.java:186)
      at org.junit.runners.Parameterized$TestClassRunnerForParameters.createTest(Parameterized.java:181)
      at org.junit.runners.BlockJUnit4ClassRunner$1.runReflectiveCall(BlockJUnit4ClassRunner.java:244)
      at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
      at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:241)
      at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
      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.junit.runners.ParentRunner.run(ParentRunner.java:309)
      at org.junit.runners.Suite.runChild(Suite.java:127)
      at org.junit.runners.Suite.runChild(Suite.java:26)
      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.junit.runners.ParentRunner.run(ParentRunner.java:309)
      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)
  </code></pre>
  
  <p>/<strong><em>*</em>**<em>*</em>***</strong><em>ignore below</em><strong><em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>***</strong>/
  adding more details
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