Is there a way to use doubleColon to invoke second level method.
Example ClassA::getClassBObject::classBMethod in lambda invocation
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Ravisha
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Did you try ClassA.getClassBObject()::classBMethod? – JavaTechnical May 08 '20 at 06:07
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Does [this answer](https://stackoverflow.com/questions/29146199/java-8-chained-method-reference) your question? Summary: no, duplicate method references are not allowed – Nowhere Man May 08 '20 at 06:12
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@JavaTechnical that simply doesnt work. getClassBObject isnt a static method – Ravisha May 08 '20 at 06:28
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@Ravisha I have posted as an example, if it isn't a static method, use the reference instead. – JavaTechnical May 08 '20 at 06:31
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@JavaTechnical that is the whole point of this question isn't it? – Ravisha May 08 '20 at 06:43
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What you are expecting is called chaining. Method references does not support chaining.
Read more about Method References.
Aniket Sahrawat
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You could compose the functions:
((Function<ClassA, ClassB>) ClassA::getClassBObject).andThen(ClassB::classBMethod)
But you're probably better off with just (x, arg) -> x.getClassBObject().classBMethod(arg).
More info on the composition approach: https://stackoverflow.com/a/32838924/2093695
Brian McCutchon
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no need to downvote. He mentioned that it is a solution but not a good one – Ravisha May 08 '20 at 06:26
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@roundAbout I posted it because it's interesting, not because it's a good idea in real code. If anything, I think my answer shows by counterexample why you should just use a regular lambda. – Brian McCutchon May 08 '20 at 06:45