jcr/CollectionNodeIterator.java

   1 package org.argeo.jcr;
   2
   3 import java.util.Collection;
   4 import java.util.Iterator;
   5 import java.util.NoSuchElementException;
   6
   7 import javax.jcr.Node;
   8 import javax.jcr.NodeIterator;
   9
  10 /** Wraps a collection of nodes in order to read it as a {@link NodeIterator} */
  11 public class CollectionNodeIterator implements NodeIterator {
  12         private final Long collectionSize;
  13         private final Iterator<Node> iterator;
  14         private Integer position = 0;
  15
  16         public CollectionNodeIterator(Collection<Node> nodes) {
  17                 super();
  18                 this.collectionSize = (long) nodes.size();
  19                 this.iterator = nodes.iterator();
  20         }
  21
  22         public void skip(long skipNum) {
  23                 if (skipNum < 0)
  24                         throw new IllegalArgumentException(
  25                                         "Skip count has to be positive: " + skipNum);
  26
  27                 for (long i = 0; i < skipNum; i++) {
  28                         if (!hasNext())
  29                                 throw new NoSuchElementException("Last element past (position="
  30                                                 + getPosition() + ")");
  31                         nextNode();
  32                 }
  33         }
  34
  35         public long getSize() {
  36                 return collectionSize;
  37         }
  38
  39         public long getPosition() {
  40                 return position;
  41         }
  42
  43         public boolean hasNext() {
  44                 return iterator.hasNext();
  45         }
  46
  47         public Object next() {
  48                 return nextNode();
  49         }
  50
  51         public void remove() {
  52                 iterator.remove();
  53         }
  54
  55         public Node nextNode() {
  56                 Node node = iterator.next();
  57                 position++;
  58                 return node;
  59         }
  60
  61 }