New project conventions

[lgpl/argeo-commons.git] / org.argeo.server.jcr / src / org / argeo / jcr / CollectionNodeIterator.java

diff --git a/org.argeo.server.jcr/src/org/argeo/jcr/CollectionNodeIterator.java b/org.argeo.server.jcr/src/org/argeo/jcr/CollectionNodeIterator.java
new file mode 100644 (file)
index 0000000..a65907a
--- /dev/null
+++ b/org.argeo.server.jcr/src/org/argeo/jcr/CollectionNodeIterator.java
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2007-2012 Argeo GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.argeo.jcr;
+
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+import javax.jcr.Node;
+import javax.jcr.NodeIterator;
+
+/** Wraps a collection of nodes in order to read it as a {@link NodeIterator} */
+public class CollectionNodeIterator implements NodeIterator {
+       private final Long collectionSize;
+       private final Iterator<Node> iterator;
+       private Integer position = 0;
+
+       public CollectionNodeIterator(Collection<Node> nodes) {
+               super();
+               this.collectionSize = (long) nodes.size();
+               this.iterator = nodes.iterator();
+       }
+
+       public void skip(long skipNum) {
+               if (skipNum < 0)
+                       throw new IllegalArgumentException(
+                                       "Skip count has to be positive: " + skipNum);
+
+               for (long i = 0; i < skipNum; i++) {
+                       if (!hasNext())
+                               throw new NoSuchElementException("Last element past (position="
+                                               + getPosition() + ")");
+                       nextNode();
+               }
+       }
+
+       public long getSize() {
+               return collectionSize;
+       }
+
+       public long getPosition() {
+               return position;
+       }
+
+       public boolean hasNext() {
+               return iterator.hasNext();
+       }
+
+       public Object next() {
+               return nextNode();
+       }
+
+       public void remove() {
+               iterator.remove();
+       }
+
+       public Node nextNode() {
+               Node node = iterator.next();
+               position++;
+               return node;
+       }
+
+}