Mocking a Supplier<>-Bean

I would like to mock a Bean (using mockito) that is defined like so

@Bean("idGenerator")
public Supplier<UUID> idGenerator() {
  return () -> UUID.randomUUID();
}

In a SpringBootTest-class I get an error using @MockBean indicating, that that Bean cannot be mocked (due to some limitations in the JVM? - sorry, I don't have the stacktrace at hand right now).

I came up with a workaround that does not use Mocks but an additional field in a @TestConfiguration so that the return-value of the supplier can be specified externally.

Since I don't rea开发者_运维百科lly like that workaround (and my colleagues won't either), I hope there is a proved pattern or the realization I am doing that mocking wrong.

You can just define it like follows:

@MockBean(name = "idGenerator")
private Supplier<UUID> mockedSupplier;

there is no issue that prevents this from mocking. Would be good to include your stacktrace, as the issue is probably somewhere else.