@Test( expected = EnvironmentCreationException.class )
public void testExecute() throws Exception
{

    doReturn( true ).when( step ).processResponse( any( CreateEnvironmentContainersResponse.class ), anyString() );
    step.execute();
    verify( PEER_UTIL ).addPeerTask( any( PeerUtil.PeerTask.class ) );
    doReturn( false ).when( step ).processResponse( any( CreateEnvironmentContainersResponse.class ), anyString() );
    step.execute();
}