MessageHeaderAccessor doesn't remove headers if they are null [SPR-14468]

[spring-projects-issues]

Artem Bilan opened SPR-14468 and commented

The test-case to reproduce:

@Test
public void testRemoveEvenIfNull() {
	Message<?> message = new GenericMessage<>("payload", Collections.singletonMap("foo", null));
	MessageHeaderAccessor accessor = new MessageHeaderAccessor(message);
	accessor.removeHeader("foo");
	Map<String, Object> headers = accessor.toMap();
	assertFalse(headers.containsKey("foo"));
}

The workaround is only to extract a target Map and remove from there, and build a new Message.

But that doesn't help for Spring Integration's HeaderFilter to work properly.

---

Affects: 4.2.7, 4.3.1

Backported to: 4.2.8

[spring-projects-issues]

Juergen Hoeller commented

Good catch there! Even if MessageHeaderAccessor isn't really designed for storing null values there (implying that null means removal for its own accessor methods), it should properly handle them when encountered in the underlying Map.

[spring-projects-issues]

Artem Bilan commented

Perfect turnaround, Juergen :)!

Thank you!

[spring-projects-issues]

Juergen Hoeller commented

You're welcome :-)

BTW, this is just in master at the moment. I'll backport it along with a few others tomorrow.