java.util
Interface Enumeration
-
- All Known Subinterfaces:
- NamingEnumeration
- All Known Implementing Classes:
- StringTokenizer
public interface Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time. Successive calls to thenextElement
method return successive elements of the series.For example, to print all elements of a Vectorv:
for (Enumeration
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 ae = v.elements(); e.hasMoreElements();) System.out.println(e.nextElement()); 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
- See Also:
Iterator
,SequenceInputStream
,nextElement()
,Hashtable
,Hashtable.elements()
,Hashtable.keys()
,Vector
,Vector.elements()
Method Summary
Modifier and Type Method and Description 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 Detail
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.
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