Unit testing a Spring.io Validator class with ValidationContext

unitTestSpringValidationClass

@Test
public void testValidateInitialDetailsCapture() {
	
	MyModel myModel = new MyModel();
	
	// setup:
	MyModel.setSomeField("Some Value");
	
	// this is the line that stumped me
	ValidationContext validationContext = new DefaultValidationContext(requestContext, null, null);
	
	MyModelValidator myModelValidator = new MyModelValidator();
	myModelValidator.validateInitialSomeState(
			myModel, validationContext);

	MessageContext messages = requestContext.getMessageContext();
	assertEquals(1, messages.getAllMessages().length);
	//... other assertions go here
}