JUnit test that verifies that a class cannot be instantiated

gistfile1.txt

Given class...

public class MyClass {
    
    private MyClass() throws InstantiationException {
        throw new InstantiationException("Instances of this type are forbidden.");    
    }

    ... 

}

This is the test to ensure class cannot be instantiated...

    @Test
    public void test_no_instantiations() throws Exception {
        Constructor constructor = MyClass.class.getDeclaredConstructors()[0];
        constructor.setAccessible(true);
        try {
            constructor.newInstance((Object[])null);
            fail("Expected construction failure");
        } catch (InvocationTargetException ex) {
            Throwable targetException = ex.getTargetException();
            assertNotNull(targetException);
            assertEquals(targetException.getClass(), InstantiationException.class);
        }
    }