1 | package org.farng.mp3.filename; |
2 | |
3 | import java.util.Iterator; |
4 | import java.util.NoSuchElementException; |
5 | |
6 | /** |
7 | * This class is an iterator for the <code>FilenameDelimiter</code> class. |
8 | * |
9 | * @author Eric Farng |
10 | * @version $Revision: 1.1 $ |
11 | */ |
12 | public class FilenameDelimiterIterator implements Iterator { |
13 | |
14 | /** |
15 | * iterator for the composite before the delimiter |
16 | */ |
17 | private Iterator afterIterator = null; |
18 | /** |
19 | * iterator for the composite after the delimiter |
20 | */ |
21 | private Iterator beforeIterator = null; |
22 | |
23 | /** |
24 | * Creates a new FilenameDelimiterIterator object. |
25 | * |
26 | * @param filenameDelimiter FilenameDelimiter to create an interator from. |
27 | */ |
28 | public FilenameDelimiterIterator(final FilenameDelimiter filenameDelimiter) { |
29 | super(); |
30 | if (filenameDelimiter.getBeforeComposite() != null) { |
31 | beforeIterator = filenameDelimiter.getBeforeComposite().iterator(); |
32 | } |
33 | if (filenameDelimiter.getAfterComposite() != null) { |
34 | afterIterator = filenameDelimiter.getAfterComposite().iterator(); |
35 | } |
36 | } |
37 | |
38 | /** |
39 | * Returns true if the iteration has more elements. (In other words, returns true if next would return an element |
40 | * rather than throwing an exception.) |
41 | * |
42 | * @return true if the iteration has more elements |
43 | */ |
44 | public boolean hasNext() { |
45 | boolean nextFlag = false; |
46 | if (beforeIterator != null) { |
47 | nextFlag = beforeIterator.hasNext(); |
48 | } |
49 | if (afterIterator != null) { |
50 | nextFlag = nextFlag || afterIterator.hasNext(); |
51 | } |
52 | return nextFlag; |
53 | } |
54 | |
55 | /** |
56 | * Returns the next element in the iteration. |
57 | * |
58 | * @return the next element in the iteration. |
59 | */ |
60 | public Object next() { |
61 | if (beforeIterator != null && beforeIterator.hasNext()) { |
62 | return beforeIterator.next(); |
63 | } else if (afterIterator != null && afterIterator.hasNext()) { |
64 | return afterIterator.next(); |
65 | } else { |
66 | throw new NoSuchElementException("Iteration has no more elements."); |
67 | } |
68 | } |
69 | |
70 | /** |
71 | * This method is not supported in this iterator. |
72 | * |
73 | * @throws UnsupportedOperationException This method is not supported in this iterator |
74 | */ |
75 | public void remove() { |
76 | //todo Implement this java.util.Iterator method |
77 | throw new UnsupportedOperationException("Method remove() not yet implemented."); |
78 | } |
79 | } |