BinaryOperator (Java SE 9 & JDK 9 )
Keywords: java.util.function.BinaryOperator interface

Module java.base
Package java.util.function

## Interface BinaryOperator<T>

- Type Parameters:
    `T` - the type of the operands and result of the operator
  All Superinterfaces:
    `BiFunction<T,T,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 BinaryOperator<T>
      extends BiFunction<T,T,T>

  Represents an operation upon two operands of the same type, producing a result of the same type as the operands. This is a specialization of `BiFunction` for the case where the operands and the result are all of the same type.

  This is a functional interface whose functional method is `BiFunction.apply(Object, Object)`.

  Since:
    1.8
  See Also:
    `BiFunction`, `UnaryOperator`

- - ### Method Summary

    All Methods Static Methods Default Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `static <T> BinaryOperator<T>` | `maxBy​(Comparator<? super T> comparator)` | Returns a `BinaryOperator` which returns the greater of two elements according to the specified `Comparator`.
    `static <T> BinaryOperator<T>` | `minBy​(Comparator<? super T> comparator)` | Returns a `BinaryOperator` which returns the lesser of two elements according to the specified `Comparator`.

    - ### Methods inherited from interface java.util.function.BiFunction

      `andThen, apply`

- - ### Method Detail

    - #### minBy

          static <T> BinaryOperator<T> minBy​(Comparator<? super T> comparator)

      Returns a `BinaryOperator` which returns the lesser of two elements according to the specified `Comparator`.
      Type Parameters:
        `T` - the type of the input arguments of the comparator
      Parameters:
        `comparator` - a `Comparator` for comparing the two values
      Returns:
        a `BinaryOperator` which returns the lesser of its operands, according to the supplied `Comparator`
      Throws:
        `NullPointerException` - if the argument is null

    - #### maxBy

          static <T> BinaryOperator<T> maxBy​(Comparator<? super T> comparator)

      Returns a `BinaryOperator` which returns the greater of two elements according to the specified `Comparator`.
      Type Parameters:
        `T` - the type of the input arguments of the comparator
      Parameters:
        `comparator` - a `Comparator` for comparing the two values
      Returns:
        a `BinaryOperator` which returns the greater of its operands, according to the supplied `Comparator`
      Throws:
        `NullPointerException` - if the argument is null