@Test
 public void checkThatOtherMethodsAreNonStatic() throws NoSuchMethodException {
   Method spin = Earth.class.getDeclaredMethod("spin");
   assertFalse("Method spin() should not be static", Modifier.isStatic(spin.getModifiers()));
   Method warmUp = Earth.class.getDeclaredMethod("warmUp");
   assertFalse("Method warmUp() should not be static", Modifier.isStatic(warmUp.getModifiers()));
 }
  private Method findPublicVoidMethod(Class<?> aClass, String methodName) {
    for (Method method : aClass.getDeclaredMethods()) {
      if (isPublic(method.getModifiers())
          && method.getReturnType() == void.class
          && methodName.equals(method.getName())) {
        return method;
      }
    }

    return null;
  }
 private Method checkThatSingletonContainsStaticInstanceAccessorMethod(Class clazz) {
   for (Method method : clazz.getDeclaredMethods()) {
     if (method.getReturnType() == clazz && method.getParameterTypes().length == 0) {
       assertTrue(
           "Method returning the Earth instance should be static",
           Modifier.isStatic(method.getModifiers()));
       return method;
     }
   }
   fail("No static accessor method found.");
   return null; // will never be called.
 }