@Test
	public void testCannotInsertExistingItem() {
		UnitOfWork<UnitItem> unit = new UnitOfWork<>();
		
		UnitItem item = new UnitItem();
		item.setValue("Foo");
		item.setId(345);
		
		try {
			unit.insert(item);
		} catch(IllegalArgumentException exception) {
			Assert.assertEquals("The record 'Foo' is already in the data model and cannot be inserted again.", exception.getMessage());
		}
	}