Package org.apache.commons.functor.core.collection

Class TransformedIterator<E,​T>

  • Type Parameters:
    E - the function argument type
    T - the iterator elements type
    All Implemented Interfaces:
    java.util.Iterator<T>
    public final class TransformedIterator<E,​T>
extends java.lang.Object
implements java.util.Iterator<T>
    Iterator that transforms another Iterator by applying a UnaryFunction to each returned element.
    Version:
    $Revision$ $Date$

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private UnaryFunction<? super E,​? extends T> function
      The function to apply to each iterator element.
      private java.util.Iterator<? extends E> iterator
      The wrapped iterator.

    • Constructor Summary

      Constructors 
      Constructor Description
      TransformedIterator​(java.util.Iterator<? extends E> iterator, UnaryFunction<? super E,​? extends T> function)
      Create a new TransformedIterator.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean equals​(java.lang.Object obj)
      int hashCode()
      boolean hasNext()
      static <E> java.util.Iterator<?> maybeTransform​(java.util.Iterator<? extends E> iter, UnaryFunction<? super E,​?> func)
      Get an Iterator instance that may be transformed.
      T next()
      void remove()
      java.lang.String toString()
      static <E,​T>
      java.util.Iterator<T>      		 transform​(java.util.Iterator<? extends E> iter, UnaryFunction<? super E,​? extends T> func)
      Get a Transformed Iterator instance.

      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.util.Iterator

        forEachRemaining

    • Field Detail

      • function

        private final UnaryFunction<? super E,​? extends T> function
        The function to apply to each iterator element.

      • iterator

        private final java.util.Iterator<? extends E> iterator
        The wrapped iterator.

    • Constructor Detail

      • TransformedIterator

        public TransformedIterator​(java.util.Iterator<? extends E> iterator,
                           UnaryFunction<? super E,​? extends T> function)
        Create a new TransformedIterator.
        Parameters:
        iterator - Iterator to decorate
        function - to apply

    • Method Detail

      • hasNext

        public boolean hasNext()
        Specified by:
        hasNext in interface java.util.Iterator<E>
        See Also:
        Iterator.hasNext()

      • next

        public T next()
        Specified by:
        next in interface java.util.Iterator<E>
        See Also:
        Iterator.next()

      • remove

        public void remove()
        Specified by:
        remove in interface java.util.Iterator<E>
        See Also:
        Iterator.remove()

      • equals

        public boolean equals​(java.lang.Object obj)
        Overrides:
        equals in class java.lang.Object

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • transform

        public static <E,​T> java.util.Iterator<T> transform​(java.util.Iterator<? extends E> iter,
                                                          UnaryFunction<? super E,​? extends T> func)
        Get a Transformed Iterator instance.
        Type Parameters:
        E - the function argument type
        T - the iterator elements type
        Parameters:
        iter - to decorate, if null result is null
        func - transforming function, cannot be null
        Returns:
        Iterator

      • maybeTransform

        public static <E> java.util.Iterator<?> maybeTransform​(java.util.Iterator<? extends E> iter,
                                                       UnaryFunction<? super E,​?> func)
        Get an Iterator instance that may be transformed.
        Type Parameters:
        E - the iterator elements type
        Parameters:
        iter - to decorate, if null result is null
        func - transforming function, if null result is iter
        Returns:
        Iterator