java.util.Enumeration Maven / Gradle / Ivy
/*
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This work corresponds to the API signatures of JSR 219: Foundation
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*/
package java.util;
/**
* 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: java.io.SequenceInputStream is found in J2ME CDC profiles such as
* J2ME Foundation Profile.
*
* 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.
*
* @see java.util.Iterator
* @see java.io.SequenceInputStream
* @see java.util.Enumeration#nextElement()
* @see java.util.Hashtable
* @see java.util.Hashtable#elements()
* @see java.util.Hashtable#keys()
* @see java.util.Vector
* @see java.util.Vector#elements()
*
* @author Lee Boynton
* @version 1.18, 02/02/00
* @since JDK1.0
*/
public interface Enumeration
{
/**
* Tests if this enumeration contains more elements.
*
* @return true if and only if this enumeration object
* contains at least one more element to provide;
* false otherwise.
*/
public boolean hasMoreElements();
/**
* Returns the next element of this enumeration if this enumeration
* object has at least one more element to provide.
*
* @return the next element of this enumeration.
* @exception NoSuchElementException if no more elements exist.
*/
public Object nextElement();
}