Interface ThrowingFunction<T,R>

Type Parameters:
T - the type of the input to the function
R - the type of the result of the function
All Superinterfaces:
Function<T,R>
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 ThrowingFunction<T,R> extends Function<T,R>
A Function that allows invocation of code that throws a checked exception.
Since:
6.0
Author:
Stephane Nicoll, Phillip Webb
  • Method Details

    • applyWithException

      R applyWithException(T t) throws Exception
      Applies this function to the given argument, possibly throwing a checked exception.
      Parameters:
      t - the function argument
      Returns:
      the function result
      Throws:
      Exception - on error
    • apply

      default R apply(T t)
      Default Function.apply(Object) that wraps any thrown checked exceptions (by default in a RuntimeException).
      Specified by:
      apply in interface Function<T,R>
      See Also:
    • apply

      default R apply(T t, BiFunction<String,Exception,RuntimeException> exceptionWrapper)
      Applies this function to the given argument, wrapping any thrown checked exceptions using the given exceptionWrapper.
      Parameters:
      exceptionWrapper - BiFunction that wraps the given message and checked exception into a runtime exception
      Returns:
      a result
    • throwing

      default ThrowingFunction<T,R> throwing(BiFunction<String,Exception,RuntimeException> exceptionWrapper)
      Return a new ThrowingFunction where the apply(Object) method wraps any thrown checked exceptions using the given exceptionWrapper.
      Parameters:
      exceptionWrapper - BiFunction that wraps the given message and checked exception into a runtime exception
      Returns:
      the replacement ThrowingFunction instance
    • of

      static <T, R> ThrowingFunction<T,R> of(ThrowingFunction<T,R> function)
      Lambda friendly convenience method that can be used to create a ThrowingFunction where the apply(Object) method wraps any checked exception thrown by the supplied lambda expression or method reference.

      This method can be especially useful when working with method references. It allows you to easily convert a method that throws a checked exception into an instance compatible with a regular Function.

      For example:

       stream.map(ThrowingFunction.of(Example::methodThatCanThrowCheckedException));
       
      Type Parameters:
      T - the type of the input to the function
      R - the type of the result of the function
      Parameters:
      function - the source function
      Returns:
      a new ThrowingFunction instance
    • of

      static <T, R> ThrowingFunction<T,R> of(ThrowingFunction<T,R> function, BiFunction<String,Exception,RuntimeException> exceptionWrapper)
      Lambda friendly convenience method that can be used to create a ThrowingFunction where the apply(Object) method wraps any thrown checked exceptions using the given exceptionWrapper.

      This method can be especially useful when working with method references. It allows you to easily convert a method that throws a checked exception into an instance compatible with a regular Function.

      For example:

       stream.map(ThrowingFunction.of(Example::methodThatCanThrowCheckedException, IllegalStateException::new));
       
      Type Parameters:
      T - the type of the input to the function
      R - the type of the result of the function
      Parameters:
      function - the source function
      exceptionWrapper - the exception wrapper to use
      Returns:
      a new ThrowingFunction instance