java.util

Interface Enumeration<E>

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 v:

     for (Enumeration 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.

NOTE: The functionality of this interface is duplicated by the Iterator interface. In addition, Iterator adds an optional remove operation, and has shorter method names. New implementations should consider using Iterator in preference to Enumeration.

Since: JDK1.0

Version: 1.21, 02/17/03

Author: Lee Boynton

See Also: Iterator java.io.SequenceInputStream nextElement Hashtable elements keys Vector elements

Method Summary
booleanhasMoreElements()
Tests if this enumeration contains more elements.
EnextElement()
Returns the next element of this enumeration if this enumeration object has at least one more element to provide.

Method Detail

hasMoreElements

public 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

public 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.