@Test
public void testMultiply() {

  final Vector2 vec1 = new Vector2(1, -1);
  final Vector2 vec2 = vec1.multiply(2.0, null);
  final Vector2 vec2B = vec1.multiply(2.0, new Vector2());
  assertEquals(new Vector2(2.0, -2.0), vec2);
  assertEquals(new Vector2(2.0, -2.0), vec2B);
  vec2.multiplyLocal(0.5);
  assertEquals(new Vector2(1.0, -1.0), vec2);
  final Vector2 vec3 = vec1.multiply(vec2, null);
  final Vector2 vec3B = vec1.multiply(vec2, new Vector2());
  assertEquals(Vector2.ONE, vec3);
  assertEquals(Vector2.ONE, vec3B);
  final Vector2 vec4 = vec1.multiply(2, 3, null);
  final Vector2 vec4B = vec1.multiply(2, 3, new Vector2());
  assertEquals(new Vector2(2, -3), vec4);
  assertEquals(new Vector2(2, -3), vec4B);
  vec1.multiplyLocal(0.5, 0.5);
  assertEquals(new Vector2(0.5, -0.5), vec1);
  vec1.multiplyLocal(vec2);
  assertEquals(new Vector2(0.5, 0.5), vec1);
}