Consumer (Java SE 14 & JDK 14)
Description: declaration: module: java.base, package: java.util.function, interface: Consumer
Keywords: java.util.function.Consumer interface

Module java.base
Package java.util.function

# Interface Consumer<T>

Type Parameters:
  `T` - the type of the input to the operation

All Known Subinterfaces:
  `Stream.Builder<T>`

Functional Interface:
  This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

    @FunctionalInterface
    public interface Consumer<T>

Represents an operation that accepts a single input argument and returns no result. Unlike most other functional interfaces, `Consumer` is expected to operate via side-effects.

This is a functional interface whose functional method is `accept(Object)`.

Since:
  1.8

- ## Method Summary

  Modifier and Type | Method | Description
  --- | --- | ---
  `void` | `accept​(T t)` | Performs this operation on the given argument.
  `default Consumer<T>` | `andThen​(Consumer<? super T> after)` | Returns a composed `Consumer` that performs, in sequence, this operation followed by the `after` operation.

- ## Method Details

  - ### accept

    void accept​(T t)
    Performs this operation on the given argument.
    Parameters:
      `t` - the input argument

  - ### andThen

    default Consumer<T> andThen​(Consumer<? super T> after)
    Returns a composed `Consumer` that performs, in sequence, this operation followed by the `after` operation. If performing either operation throws an exception, it is relayed to the caller of the composed operation. If performing this operation throws an exception, the `after` operation will not be performed.
    Parameters:
      `after` - the operation to perform after this operation
    Returns:
      a composed `Consumer` that performs in sequence this operation followed by the `after` operation
    Throws:
      `NullPointerException` - if `after` is null