Module com.jongsoft.lang
Package com.jongsoft.lang

Interface Value<T>

  • Type Parameters:
    T - the type of object being wrapped
    All Superinterfaces:
    java.lang.Iterable<T>, java.io.Serializable, Streamable<T>
    All Known Subinterfaces:
    Collection<T>, Iterator<T>, List<T>, Map<K,​T>, Optional<T>, Sequence<T>, Set<T>, Traversable<T>, Tree<T>, Tree.NodeCollection<T>
    All Known Implementing Classes:
    ValueType
    public interface Value<T>
extends Streamable<T>, java.io.Serializable
    The Value interface represents a simple wrapped value. This interface can contain exactly one entity inside, or None in case of an empty value.
    Since:
    0.0.1

    • Method Summary

      All Methods Instance Methods Abstract Methods Default Methods 
      Modifier and Type Method Description
      default boolean all​(java.util.function.Predicate<? super T> predicate)
      Validate that all elements match the predicate provided.
      default boolean contains​(T element)
      Validate if the value contains the provided item.
      default boolean exists​(java.util.function.Predicate<? super T> predicate)
      Validate if an element is contained that matches the provided predicate.
      T get()
      Return the contents T of the wrapped value.
      boolean isSingleValued()
      Is this instance single-valued or not.
      default boolean none​(java.util.function.Predicate<? super T> predicate)
      Validate that none of the elements match the predicate provided.
      default java.util.stream.Stream<T> stream()
      Create a stream of the value.

      • Methods inherited from interface java.lang.Iterable

        forEach, iterator, spliterator

    • Method Detail

      • all

        default boolean all​(java.util.function.Predicate<? super T> predicate)
        Validate that all elements match the predicate provided. This can be useful to quickly look over the elements to verify that they all meet a pre-specified criteria.

        Example:

           // result will be true
    List("a", "b").all(x -> x.length() == 1);
        Parameters:
        predicate - the predicate to test with
        Returns:
        true if all elements match the predicate, otherwise false
        Throws:
        java.lang.NullPointerException - in case the Predicate is null
        See Also:
        none(Predicate), exists(Predicate)

      • contains

        default boolean contains​(T element)
        Validate if the value contains the provided item.
        Parameters:
        element - an element of type T, can be null
        Returns:
        true, if the element is contained within

      • exists

        default boolean exists​(java.util.function.Predicate<? super T> predicate)
        Validate if an element is contained that matches the provided predicate.
        Parameters:
        predicate - the predicate to validate with
        Returns:
        true, if any element is contained within that matches the predicate
        Throws:
        java.lang.NullPointerException - in case the Predicate is null

      • get

        T get()
        Return the contents T of the wrapped value.

        This can throw a NoSuchElementException if no value is present.

        Returns:
        returns the object wrapped in this value
        Throws:
        java.util.NoSuchElementException - if no element is present

      • isSingleValued

        boolean isSingleValued()
        Is this instance single-valued or not.
        Returns:
        true if single-valued, otherwise false

      • none

        default boolean none​(java.util.function.Predicate<? super T> predicate)
        Validate that none of the elements match the predicate provided.
        Parameters:
        predicate - the predicate to test with
        Returns:
        true if none of the elements match, otherwise false
        Throws:
        java.lang.NullPointerException - in case the Predicate is null
        See Also:
        all(Predicate), exists(Predicate)

      • stream

        default java.util.stream.Stream<T> stream()
        Create a stream of the value.
        Specified by:
        stream in interface Streamable<T>
        Returns:
        the stream containing the value