@Test
	public void testMaskPropertiesIfNecessaryWithNullProperties() {
		try {
			PasswordUtils.maskPropertiesIfNecessary(null);
		}
		catch (IllegalArgumentException e) {
			assertEquals("'properties' must not be null.", e.getMessage());
			return;
		}
		fail("Expected an IllegalArgumentException to be thrown");
	}
A basic stream definition parameter (parameter in middle of stream) called "password" with value wrapped in quotes should have its value masked
spring-xd-dirt/src/test/java/org/springframework/xd/dirt/rest/PasswordUtilsTests.java