Module java.base
Package java.util

Interface Enumeration<E>

Type Parameters:
E - the type of elements returned by this enumeration
All Known Subinterfaces:
NamingEnumeration<T>
All Known Implementing Classes:
StringTokenizer
public interface Enumeration<E>
An object that implements the Enumeration interface generates a series of elements, one at a time. Successive calls to the nextElement method return successive elements of the series.

For example, to print all elements of a Vector<E> v: 

   for (Enumeration<E> e = v.elements(); e.hasMoreElements();)
       System.out.println(e.nextElement());

Methods are provided to enumerate through the elements of a vector, the keys of a hashtable, and the values in a hashtable. Enumerations are also used to specify the input streams to a SequenceInputStream.

Since:
1.0
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    default Iterator<E>
    asIterator()
    Returns an Iterator that traverses the remaining elements covered by this enumeration.
    boolean
    hasMoreElements()
    Tests if this enumeration contains more elements.
    E
    nextElement()
    Returns the next element of this enumeration if this enumeration object has at least one more element to provide.

  • Method Details

    • hasMoreElements

      boolean hasMoreElements()
      Tests if this enumeration contains more elements.
      Returns:
      true if and only if this enumeration object contains at least one more element to provide; false otherwise.

    • nextElement

      E nextElement()
      Returns the next element of this enumeration if this enumeration object has at least one more element to provide.
      Returns:
      the next element of this enumeration.
      Throws:
      NoSuchElementException - if no more elements exist.

    • asIterator

      default Iterator<E> asIterator()
      Returns an Iterator that traverses the remaining elements covered by this enumeration. Traversal is undefined if any methods are called on this enumeration after the call to asIterator.
      Returns:
      an Iterator representing the remaining elements of this Enumeration
      Since:
      9