Consumer (Java Platform SE 8 ) (original) (raw)

• Type Parameters:
  T - the type of the input to the operation
  All Known Subinterfaces:
  Stream.Builder
  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
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

  All Methods Instance Methods Abstract Methods Default Methods

  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 Detail

     * #### accept  
     void accept([T](../../../java/util/function/Consumer.html "type parameter in Consumer") t)  
     Performs this operation on the given argument.  
     Parameters:  
     `t` \- the input argument  
     * #### andThen  
     default [Consumer](../../../java/util/function/Consumer.html "interface in java.util.function")<[T](../../../java/util/function/Consumer.html "type parameter in Consumer")> andThen([Consumer](../../../java/util/function/Consumer.html "interface in java.util.function")<? super [T](../../../java/util/function/Consumer.html "type parameter in Consumer")> 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](../../../java/lang/NullPointerException.html "class in java.lang")` \- if `after` is null

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