src/broken/AmbiguousNullTombstone.java:9: error: reference to pipeInput is ambiguous
        blocked.pipeInput("c5", null);
               ^
  both method pipeInput(K,V) in TestInputTopic and method pipeInput(V,Instant) in TestInputTopic match
  where K,V are type-variables:
    K extends Object declared in class TestInputTopic
    V extends Object declared in class TestInputTopic
1 error