ParticleElement extends Region { public void move() { location.add(velocity); } ParticleElement(ParticleVector location, ParticleVector velocity,
            double width, double height, Image image); void move(); void display(); void age(); ParticleVector getLocation(); Image getTexture(); Boolean isDead(double pointX, double pointY); boolean isDead(int deathTime); @Override boolean isResizable();  }
@Test public void testMove() { ParticleElement particle = new ParticleElement( new ParticleVector(), new ParticleVector(1, 1), 20, 20, null); particle.move(); Assert.assertEquals(new ParticleVector(1, 1), particle.getLocation()); particle.move(); Assert.assertEquals(new ParticleVector(2, 2), particle.getLocation()); }