Interface CheckedFunction2<T1,T2,R>

Type Parameters:
T1 - argument 1 of the function
T2 - argument 2 of the function
R - return type of the function
All Superinterfaces:
Serializable
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 CheckedFunction2<T1,T2,R> extends Serializable
Represents a function with two arguments.

  • Field Details

  • Method Details

    • constant

      static <T1,T2,R> CheckedFunction2<T1,T2,R> constant(R value)
      Returns a function that always returns the constant value that you give in parameter.
      Type Parameters:
      T1 - generic parameter type 1 of the resulting function
      T2 - generic parameter type 2 of the resulting function
      R - the result type
      Parameters:
      value - the value to be returned
      Returns:
      a function always returning the given value

    • of

      static <T1,T2,R> CheckedFunction2<T1,T2,R> of(CheckedFunction2<T1,T2,R> methodReference)
      Creates a CheckedFunction2 based on Examples (w.l.o.g. referring to Function1): 
      // using a lambda expression
Function1<Integer, Integer> add1 = Function1.of(i -> i + 1);

// using a method reference (, e.g. Integer method(Integer i) { return i + 1; })
Function1<Integer, Integer> add2 = Function1.of(this::method);

// using a lambda reference
Function1<Integer, Integer> add3 = Function1.of(add1::apply);

      Caution: Reflection loses type information of lambda references. 

      // type of a lambda expression
Type<?, ?> type1 = add1.getType(); // (Integer) -> Integer

// type of a method reference
Type<?, ?> type2 = add2.getType(); // (Integer) -> Integer

// type of a lambda reference
Type<?, ?> type3 = add3.getType(); // (Object) -> Object
      Type Parameters:
      T1 - 1st argument
      T2 - 2nd argument
      R - return type
      Parameters:
      methodReference - (typically) a method reference, e.g. Type::method
      Returns:
      a CheckedFunction2

    • lift

      static <T1,T2,R> Function2<T1, T2, Option<R>> lift(CheckedFunction2<? super T1, ? super T2, ? extends R> partialFunction)
      Lifts the given partialFunction into a total function that returns an Option result.
      Type Parameters:
      T1 - 1st argument
      T2 - 2nd argument
      R - return type
      Parameters:
      partialFunction - a function that is not defined for all values of the domain (e.g. by throwing)
      Returns:
      a function that applies arguments to the given partialFunction and returns Some(result) if the function is defined for the given arguments, and None otherwise.

    • liftTry

      static <T1,T2,R> Function2<T1,T2,Try<R>> liftTry(CheckedFunction2<? super T1, ? super T2, ? extends R> partialFunction)
      Lifts the given partialFunction into a total function that returns an Try result.
      Type Parameters:
      T1 - 1st argument
      T2 - 2nd argument
      R - return type
      Parameters:
      partialFunction - a function that is not defined for all values of the domain (e.g. by throwing)
      Returns:
      a function that applies arguments to the given partialFunction and returns Success(result) if the function is defined for the given arguments, and Failure(throwable) otherwise.

    • narrow

      static <T1,T2,R> CheckedFunction2<T1,T2,R> narrow(CheckedFunction2<? super T1, ? super T2, ? extends R> f)
      Narrows the given CheckedFunction2<? super T1, ? super T2, ? extends R> to CheckedFunction2<T1, T2, R>
      Type Parameters:
      T1 - 1st argument
      T2 - 2nd argument
      R - return type
      Parameters:
      f - A CheckedFunction2
      Returns:
      the given f instance as narrowed type CheckedFunction2<T1, T2, R>

    • apply

      R apply(T1 t1, T2 t2) throws Throwable
      Applies this function to two arguments and returns the result.
      Parameters:
      t1 - argument 1
      t2 - argument 2
      Returns:
      the result of function application
      Throws:
      Throwable - if something goes wrong applying this function to the given arguments

    • apply

      default CheckedFunction1<T2,R> apply(T1 t1)
      Applies this function partially to one argument.
      Parameters:
      t1 - argument 1
      Returns:
      a partial application of this function

    • arity

      default int arity()
      Returns the number of function arguments.
      Returns:
      an int value >= 0
      See Also:

    • curried

      default Function1<T1, CheckedFunction1<T2,R>> curried()
      Returns a curried version of this function.
      Returns:
      a curried function equivalent to this.

    • tupled

      default CheckedFunction1<Tuple2<T1,T2>, R> tupled()
      Returns a tupled version of this function.
      Returns:
      a tupled function equivalent to this.

    • reversed

      default CheckedFunction2<T2,T1,R> reversed()
      Returns a reversed version of this function. This may be useful in a recursive context.
      Returns:
      a reversed function equivalent to this.

    • memoized

      default CheckedFunction2<T1,T2,R> memoized()
      Returns a memoizing version of this function, which computes the return value for given arguments only one time. On subsequent calls given the same arguments the memoized value is returned.

      Please note that memoizing functions do not permit null as single argument or return value.

      Returns:
      a memoizing function equivalent to this.

    • isMemoized

      default boolean isMemoized()
      Checks if this function is memoizing (= caching) computed values.
      Returns:
      true, if this function is memoizing, false otherwise

    • recover

      default Function2<T1,T2,R> recover(Function<? super Throwable, ? extends BiFunction<? super T1, ? super T2, ? extends R>> recover)
      Return a composed function that first applies this CheckedFunction2 to the given arguments and in case of throwable try to get value from recover function with same arguments and throwable information.
      Parameters:
      recover - the function applied in case of throwable
      Returns:
      a function composed of this and recover
      Throws:
      NullPointerException - if recover is null

    • unchecked

      default Function2<T1,T2,R> unchecked()
      Returns an unchecked function that will sneaky throw if an exceptions occurs when applying the function.
      Returns:
      a new Function2 that throws a Throwable.

    • andThen

      default <V> CheckedFunction2<T1,T2,V> andThen(CheckedFunction1<? super R, ? extends V> after)
      Returns a composed function that first applies this CheckedFunction2 to the given argument and then applies CheckedFunction1 after to the result.
      Type Parameters:
      V - return type of after
      Parameters:
      after - the function applied after this
      Returns:
      a function composed of this and after
      Throws:
      NullPointerException - if after is null