@Test
 public void testIsValidShouldReturnTrueWhenStatusIsUpdated() {
   UpdateStackJson updateStackJson = new UpdateStackJson();
   updateStackJson.setInstanceGroupAdjustment(null);
   updateStackJson.setStatus(StatusRequest.STARTED);
   boolean valid = underTest.isValid(updateStackJson, constraintValidatorContext);
   assertTrue(valid);
 }
  @Test
  public void testIsValidShouldReturnFalseWhenRequestContainsOnlyNulls() {

    UpdateStackJson updateStackJson = new UpdateStackJson();
    updateStackJson.setInstanceGroupAdjustment(null);
    updateStackJson.setStatus(null);
    boolean valid = underTest.isValid(updateStackJson, constraintValidatorContext);
    assertFalse(valid);
  }
 @Test
 public void testIsValidShouldReturnFalseWhenRequestContainsNodeCountAndStatus() {
   UpdateStackJson updateStackJson = new UpdateStackJson();
   InstanceGroupAdjustmentJson instanceGroupAdjustmentJson = new InstanceGroupAdjustmentJson();
   instanceGroupAdjustmentJson.setScalingAdjustment(4);
   instanceGroupAdjustmentJson.setInstanceGroup("slave_1");
   updateStackJson.setStatus(StatusRequest.STARTED);
   updateStackJson.setInstanceGroupAdjustment(instanceGroupAdjustmentJson);
   boolean valid = underTest.isValid(updateStackJson, constraintValidatorContext);
   assertFalse(valid);
 }
 @Test
 public void testIsValidShouldReturnTrueWhenNodeCountIsUpdated() {
   UpdateStackJson updateStackJson = new UpdateStackJson();
   InstanceGroupAdjustmentJson instanceGroupAdjustmentJson = new InstanceGroupAdjustmentJson();
   instanceGroupAdjustmentJson.setScalingAdjustment(12);
   instanceGroupAdjustmentJson.setInstanceGroup("slave_1");
   updateStackJson.setInstanceGroupAdjustment(instanceGroupAdjustmentJson);
   updateStackJson.setStatus(null);
   boolean valid = underTest.isValid(updateStackJson, constraintValidatorContext);
   assertTrue(valid);
 }
 @Test
 public void testInValidShouldReturnTrueWhenNodeCountIsLowerThanOneUpdatedAndWithClusterEvent() {
   UpdateStackJson updateStackJson = new UpdateStackJson();
   InstanceGroupAdjustmentJson instanceGroupAdjustmentJson = new InstanceGroupAdjustmentJson();
   instanceGroupAdjustmentJson.setScalingAdjustment(-1);
   instanceGroupAdjustmentJson.setWithClusterEvent(true);
   instanceGroupAdjustmentJson.setInstanceGroup("slave_1");
   updateStackJson.setInstanceGroupAdjustment(instanceGroupAdjustmentJson);
   updateStackJson.setStatus(null);
   boolean valid = underTest.isValid(updateStackJson, constraintValidatorContext);
   assertFalse(valid);
 }