Callable/runnable/function with param returning void? [duplicate]

Question

What about a function that takes an argument and returns void? What is this analog called in Java?

i may be wrong on this but I'm pretty sure you can use void as a generic argument in Java. — aeskreis
– aeskreis, Commented Jul 18, 2018 at 14:14
void as a type param seems a bit hacky. I was looking for Consumer -- thanks. — Josh M.
– Josh M., Commented Jul 18, 2018 at 14:19

Nikolas · Accepted Answer · 2018-07-18 14:15:58Z

3

It's Consumer<T>. It has one input and returns void with method Consumer::accept(T t).

Represents an operation that accepts a single input argument and returns no result.

There is its variation called BiConsumer<T, U> which turns 2 inputs into void.

answered Jul 18, 2018 at 14:15

Nikolas

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Comments

vc73 · Accepted Answer · 2018-07-18 14:16:13Z

1

It's called Consumer, it's a function that takes an argument(or more), does something and doesn't return anything. For example, if you use a forEach:

exampleList.forEach(x -> System.out.println(x));

answered Jul 18, 2018 at 14:16

vc73

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Dean · Accepted Answer · 2018-07-18 14:51:32Z

1

What you are looking for is the Consumer. It is a functional interface that takes a single argument and returns void.

answered Jul 18, 2018 at 14:15

Dean

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