@Test
    public void testSetTransitionLength_zeroInput_noExceptionThrown() {
        AnimClip animClip = new AnimClip("clip");
        ClipAction clipAction = new ClipAction(animClip);
        clipAction.setTransitionLength(0);
        assertEquals(0, clipAction.getTransitionLength(), 0);
    }
Test to verify setTransitionLength on BlendableAction accepts zero.
jme3-core/src/test/java/com/jme3/anim/tween/action/ClipActionTest.java