Uses of Package java.util.function (Java Platform SE 8 )
Date: 2026-04-17

# Uses of Package
java.util.function

- Packages that use java.util.function
  Package | Description
  --- | ---
  java.lang | Provides classes that are fundamental to the design of the Java programming language.
  java.nio.file | Defines interfaces and classes for the Java virtual machine to access files, file attributes, and file systems.
  java.security | Provides the classes and interfaces for the security framework.
  java.time.temporal | Access to date and time using fields and units, and date time adjusters.
  java.util | Contains the collections framework, legacy collection classes, event model, date and time facilities, internationalization, and miscellaneous utility classes (a string tokenizer, a random-number generator, and a bit array).
  java.util.concurrent | Utility classes commonly useful in concurrent programming.
  java.util.concurrent.atomic | A small toolkit of classes that support lock-free thread-safe programming on single variables.
  java.util.function | Functional interfaces provide target types for lambda expressions and method references.
  java.util.logging | Provides the classes and interfaces of the JavaTM 2 platform's core logging facilities.
  java.util.regex | Classes for matching character sequences against patterns specified by regular expressions.
  java.util.stream | Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections.
  javax.net.ssl | Provides classes for the secure socket package.

- Classes in java.util.function used by java.lang
  Class and Description
  Consumer Represents an operation that accepts a single input argument and returns no result.
  Supplier Represents a supplier of results.

- Classes in java.util.function used by java.nio.file
  Class and Description
  BiPredicate Represents a predicate (boolean-valued function) of two arguments.

- Classes in java.util.function used by java.security
  Class and Description
  BiConsumer Represents an operation that accepts two input arguments and returns no result.
  BiFunction Represents a function that accepts two arguments and produces a result.
  Function Represents a function that accepts one argument and produces a result.

- Classes in java.util.function used by java.time.temporal
  Class and Description
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by java.util
  Class and Description
  BiConsumer Represents an operation that accepts two input arguments and returns no result.
  BiFunction Represents a function that accepts two arguments and produces a result.
  BinaryOperator Represents an operation upon two operands of the same type, producing a result of the same type as the operands.
  Consumer Represents an operation that accepts a single input argument and returns no result.
  DoubleBinaryOperator Represents an operation upon two `double`-valued operands and producing a `double`-valued result.
  DoubleConsumer Represents an operation that accepts a single `double`-valued argument and returns no result.
  DoubleSupplier Represents a supplier of `double`-valued results.
  Function Represents a function that accepts one argument and produces a result.
  IntBinaryOperator Represents an operation upon two `int`-valued operands and producing an `int`-valued result.
  IntConsumer Represents an operation that accepts a single `int`-valued argument and returns no result.
  IntFunction Represents a function that accepts an int-valued argument and produces a result.
  IntSupplier Represents a supplier of `int`-valued results.
  IntToDoubleFunction Represents a function that accepts an int-valued argument and produces a double-valued result.
  IntToLongFunction Represents a function that accepts an int-valued argument and produces a long-valued result.
  IntUnaryOperator Represents an operation on a single `int`-valued operand that produces an `int`-valued result.
  LongBinaryOperator Represents an operation upon two `long`-valued operands and producing a `long`-valued result.
  LongConsumer Represents an operation that accepts a single `long`-valued argument and returns no result.
  LongSupplier Represents a supplier of `long`-valued results.
  Predicate Represents a predicate (boolean-valued function) of one argument.
  Supplier Represents a supplier of results.
  ToDoubleFunction Represents a function that produces a double-valued result.
  ToIntFunction Represents a function that produces an int-valued result.
  ToLongFunction Represents a function that produces a long-valued result.
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by java.util.concurrent
  Class and Description
  BiConsumer Represents an operation that accepts two input arguments and returns no result.
  BiFunction Represents a function that accepts two arguments and produces a result.
  Consumer Represents an operation that accepts a single input argument and returns no result.
  DoubleBinaryOperator Represents an operation upon two `double`-valued operands and producing a `double`-valued result.
  Function Represents a function that accepts one argument and produces a result.
  IntBinaryOperator Represents an operation upon two `int`-valued operands and producing an `int`-valued result.
  LongBinaryOperator Represents an operation upon two `long`-valued operands and producing a `long`-valued result.
  Predicate Represents a predicate (boolean-valued function) of one argument.
  Supplier Represents a supplier of results.
  ToDoubleBiFunction Represents a function that accepts two arguments and produces a double-valued result.
  ToDoubleFunction Represents a function that produces a double-valued result.
  ToIntBiFunction Represents a function that accepts two arguments and produces an int-valued result.
  ToIntFunction Represents a function that produces an int-valued result.
  ToLongBiFunction Represents a function that accepts two arguments and produces a long-valued result.
  ToLongFunction Represents a function that produces a long-valued result.
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by java.util.concurrent.atomic
  Class and Description
  BinaryOperator Represents an operation upon two operands of the same type, producing a result of the same type as the operands.
  DoubleBinaryOperator Represents an operation upon two `double`-valued operands and producing a `double`-valued result.
  IntBinaryOperator Represents an operation upon two `int`-valued operands and producing an `int`-valued result.
  IntUnaryOperator Represents an operation on a single `int`-valued operand that produces an `int`-valued result.
  LongBinaryOperator Represents an operation upon two `long`-valued operands and producing a `long`-valued result.
  LongUnaryOperator Represents an operation on a single `long`-valued operand that produces a `long`-valued result.
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by java.util.function
  Class and Description
  BiConsumer Represents an operation that accepts two input arguments and returns no result.
  BiFunction Represents a function that accepts two arguments and produces a result.
  BinaryOperator Represents an operation upon two operands of the same type, producing a result of the same type as the operands.
  BiPredicate Represents a predicate (boolean-valued function) of two arguments.
  Consumer Represents an operation that accepts a single input argument and returns no result.
  DoubleConsumer Represents an operation that accepts a single `double`-valued argument and returns no result.
  DoublePredicate Represents a predicate (boolean-valued function) of one `double`-valued argument.
  DoubleUnaryOperator Represents an operation on a single `double`-valued operand that produces a `double`-valued result.
  Function Represents a function that accepts one argument and produces a result.
  IntConsumer Represents an operation that accepts a single `int`-valued argument and returns no result.
  IntPredicate Represents a predicate (boolean-valued function) of one `int`-valued argument.
  IntUnaryOperator Represents an operation on a single `int`-valued operand that produces an `int`-valued result.
  LongConsumer Represents an operation that accepts a single `long`-valued argument and returns no result.
  LongPredicate Represents a predicate (boolean-valued function) of one `long`-valued argument.
  LongUnaryOperator Represents an operation on a single `long`-valued operand that produces a `long`-valued result.
  Predicate Represents a predicate (boolean-valued function) of one argument.
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by java.util.logging
  Class and Description
  Supplier Represents a supplier of results.

- Classes in java.util.function used by java.util.regex
  Class and Description
  Predicate Represents a predicate (boolean-valued function) of one argument.

- Classes in java.util.function used by java.util.stream
  Class and Description
  BiConsumer Represents an operation that accepts two input arguments and returns no result.
  BiFunction Represents a function that accepts two arguments and produces a result.
  BinaryOperator Represents an operation upon two operands of the same type, producing a result of the same type as the operands.
  Consumer Represents an operation that accepts a single input argument and returns no result.
  DoubleBinaryOperator Represents an operation upon two `double`-valued operands and producing a `double`-valued result.
  DoubleConsumer Represents an operation that accepts a single `double`-valued argument and returns no result.
  DoubleFunction Represents a function that accepts a double-valued argument and produces a result.
  DoublePredicate Represents a predicate (boolean-valued function) of one `double`-valued argument.
  DoubleSupplier Represents a supplier of `double`-valued results.
  DoubleToIntFunction Represents a function that accepts a double-valued argument and produces an int-valued result.
  DoubleToLongFunction Represents a function that accepts a double-valued argument and produces a long-valued result.
  DoubleUnaryOperator Represents an operation on a single `double`-valued operand that produces a `double`-valued result.
  Function Represents a function that accepts one argument and produces a result.
  IntBinaryOperator Represents an operation upon two `int`-valued operands and producing an `int`-valued result.
  IntConsumer Represents an operation that accepts a single `int`-valued argument and returns no result.
  IntFunction Represents a function that accepts an int-valued argument and produces a result.
  IntPredicate Represents a predicate (boolean-valued function) of one `int`-valued argument.
  IntSupplier Represents a supplier of `int`-valued results.
  IntToDoubleFunction Represents a function that accepts an int-valued argument and produces a double-valued result.
  IntToLongFunction Represents a function that accepts an int-valued argument and produces a long-valued result.
  IntUnaryOperator Represents an operation on a single `int`-valued operand that produces an `int`-valued result.
  LongBinaryOperator Represents an operation upon two `long`-valued operands and producing a `long`-valued result.
  LongConsumer Represents an operation that accepts a single `long`-valued argument and returns no result.
  LongFunction Represents a function that accepts a long-valued argument and produces a result.
  LongPredicate Represents a predicate (boolean-valued function) of one `long`-valued argument.
  LongSupplier Represents a supplier of `long`-valued results.
  LongToDoubleFunction Represents a function that accepts a long-valued argument and produces a double-valued result.
  LongToIntFunction Represents a function that accepts a long-valued argument and produces an int-valued result.
  LongUnaryOperator Represents an operation on a single `long`-valued operand that produces a `long`-valued result.
  ObjDoubleConsumer Represents an operation that accepts an object-valued and a `double`-valued argument, and returns no result.
  ObjIntConsumer Represents an operation that accepts an object-valued and a `int`-valued argument, and returns no result.
  ObjLongConsumer Represents an operation that accepts an object-valued and a `long`-valued argument, and returns no result.
  Predicate Represents a predicate (boolean-valued function) of one argument.
  Supplier Represents a supplier of results.
  ToDoubleFunction Represents a function that produces a double-valued result.
  ToIntFunction Represents a function that produces an int-valued result.
  ToLongFunction Represents a function that produces a long-valued result.
  UnaryOperator Represents an operation on a single operand that produces a result of the same type as its operand.

- Classes in java.util.function used by javax.net.ssl
  Class and Description
  BiFunction Represents a function that accepts two arguments and produces a result.

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