Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MatchAllScorer.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MatchAllScorer.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MatchAllScorer.java	(revision )
@@ -74,59 +74,53 @@
         super(Similarity.getDefault());
         this.reader = reader;
         this.field = field;
-        matchExpl
+        matchExpl // fixme lucene (explain)
                 = new Explanation(Similarity.getDefault().idf(reader.maxDoc(),
                         reader.maxDoc()),
                         "matchAll");
         calculateDocFilter(cache);
     }
 
-    /**
-     * {@inheritDoc}
-     */
+    @Override
     public void score(Collector collector) throws IOException {
         collector.setScorer(this);
 
-        while (next()) {
-            collector.collect(doc());
+        while (nextDoc() != NO_MORE_DOCS) {
+            collector.collect(docID());
         }
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public boolean next() throws IOException {
+    @Override
+    public int nextDoc() throws IOException {
+        if (nextDoc == NO_MORE_DOCS) {
+            return nextDoc;
+        }
+
         nextDoc = docFilter.nextSetBit(nextDoc + 1);
-        return nextDoc > -1;
+        if (nextDoc < 0) {
+            nextDoc = NO_MORE_DOCS;
-    }
+        }
+        return nextDoc;
+    }
 
-    /**
-     * {@inheritDoc}
-     */
-    public int doc() {
+    @Override
+    public int docID() {
         return nextDoc;
     }
 
-    /**
-     * {@inheritDoc}
-     */
+    @Override
     public float score() throws IOException {
         return 1.0f;
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public boolean skipTo(int target) throws IOException {
-        nextDoc = target - 1;
-        return next();
+    @Override
+    public int advance(int target) throws IOException {
+        if (nextDoc == NO_MORE_DOCS) {
+            return nextDoc;
-    }
+        }
 
-    /**
-     * {@inheritDoc}
-     */
-    public Explanation explain(int doc) {
-        return matchExpl;
+        nextDoc = target - 1;
+        return nextDoc();
     }
 
     /**
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/PredicateDerefQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/PredicateDerefQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/PredicateDerefQuery.java	(revision )
@@ -16,10 +16,6 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
-import java.io.IOException;
-import java.util.BitSet;
-import java.util.Set;
-
 import org.apache.jackrabbit.core.query.lucene.hits.AbstractHitCollector;
 import org.apache.jackrabbit.spi.Name;
 import org.apache.lucene.index.IndexReader;
@@ -32,6 +28,10 @@
 import org.apache.lucene.search.Similarity;
 import org.apache.lucene.search.Weight;
 
+import java.io.IOException;
+import java.util.BitSet;
+import java.util.Set;
+
 /**
  * Implements a Lucene <code>Query</code> which returns the nodes which have a 
  * reference property which matches the nodes of the subquery.
@@ -258,49 +258,44 @@
             this.subQueryHits = new BitSet(reader.maxDoc());
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             nextDoc = hits.nextSetBit(nextDoc + 1);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             nextDoc = hits.nextSetBit(target);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * {@inheritDoc}
-         *
-         * @throws UnsupportedOperationException this implementation always
-         *                                       throws an <code>UnsupportedOperationException</code>.
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
+            return nextDoc;
         }
 
-
         /**
          * Perform the sub query
          * For each reference property UUID
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/WildcardQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/WildcardQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/WildcardQuery.java	(revision )
@@ -316,44 +316,42 @@
             hits = result;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {  
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateHits();
             nextDoc = hits.nextSetBit(nextDoc + 1);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateHits();
             nextDoc = hits.nextSetBit(target);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * Returns an empty Explanation object.
-         * @return an empty Explanation object.
-         */
-        public Explanation explain(int doc) {
-            return new Explanation();
+            return nextDoc;
         }
 
         /**
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/QueryHitsQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/QueryHitsQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/QueryHitsQuery.java	(revision )
@@ -214,48 +214,44 @@
             docs = sortedDocs.iterator();
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (currentDoc == NO_MORE_DOCS) {
+                return currentDoc;
+            }
+
             if (docs.hasNext()) {
                 currentDoc = docs.next();
-                return true;
             }
-            return false;
+            else {
+                currentDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
             return currentDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
+        public int docID() {
+            return currentDoc == null? -1 : currentDoc;
+        }
+
+        @Override
         public float score() throws IOException {
             return scores.get(currentDoc);
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (currentDoc == NO_MORE_DOCS) {
+                return currentDoc;
+            }
+
             do {
-                if (!next()) {
-                    return false;
+                if (nextDoc() == NO_MORE_DOCS) {
+                    return NO_MORE_DOCS;
                 }
-            } while (target > doc());
-            return true;
+            } while (target > docID());
+            return docID();
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public Explanation explain(int doc) throws IOException {
-            return new Explanation();
-        }
-    }
+    }
+}
-}
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/NotQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/NotQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/NotQuery.java	(revision )
@@ -17,7 +17,6 @@
 package org.apache.jackrabbit.core.query.lucene;
 
 import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.search.DocIdSetIterator;
 import org.apache.lucene.search.Explanation;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.Scorer;
@@ -180,14 +179,16 @@
             this.reader = reader;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (docNo == NO_MORE_DOCS) {
+                return docNo;
+            }
+
             if (docNo == -1) {
                 // get first doc of context scorer
                 int docId = contextScorer.nextDoc();
-                if (docId != DocIdSetIterator.NO_MORE_DOCS) {
+                if (docId != NO_MORE_DOCS) {
                     contextNo = docId;
                 }
             }
@@ -200,50 +201,45 @@
             while (contextNo != -1 && contextNo == docNo) {
                 docNo++;
                 int docId = contextScorer.nextDoc();
-                if (docId != DocIdSetIterator.NO_MORE_DOCS) {
-                    contextNo = docId;
-                } else {
+                if (docId == NO_MORE_DOCS) {
                     contextNo = -1;
+                } else {
+                    contextNo = docId;
                 }
             }
-            return docNo < reader.maxDoc();
+            if (docNo >= reader.maxDoc()) {
+                docNo = NO_MORE_DOCS;
-        }
+            }
+            return docNo;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return docNo;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (docNo == NO_MORE_DOCS) {
+                return docNo;
+            }
+
             if (contextNo != -1 && contextNo < target) {
                 int docId = contextScorer.advance(target);
-                if (docId != DocIdSetIterator.NO_MORE_DOCS) {
+                if (docId != NO_MORE_DOCS) {
                     contextNo = docId;
                 } else {
                     contextNo = -1;
                 }
             }
             docNo = target - 1;
-            return next();
+            return nextDoc();
         }
 
-        /**
-         * @throws UnsupportedOperationException always
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
-        }
-    }
+    }
+}
-}
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DescendantSelfAxisQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DescendantSelfAxisQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DescendantSelfAxisQuery.java	(revision )
@@ -16,17 +16,16 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
+import org.apache.jackrabbit.core.SessionImpl;
+import org.apache.jackrabbit.core.query.lucene.hits.AbstractHitCollector;
 import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.search.DocIdSetIterator;
 import org.apache.lucene.search.Explanation;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.Scorer;
 import org.apache.lucene.search.Searcher;
 import org.apache.lucene.search.Similarity;
-import org.apache.lucene.search.Weight;
 import org.apache.lucene.search.Sort;
-import org.apache.jackrabbit.core.SessionImpl;
-import org.apache.jackrabbit.core.query.lucene.hits.AbstractHitCollector;
+import org.apache.lucene.search.Weight;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -34,10 +33,10 @@
 import javax.jcr.RepositoryException;
 import java.io.IOException;
 import java.util.BitSet;
-import java.util.Set;
+import java.util.Iterator;
 import java.util.Map;
+import java.util.Set;
 import java.util.TreeMap;
-import java.util.Iterator;
 
 /**
  * Implements a lucene <code>Query</code> which filters a sub query by checking
@@ -431,6 +430,8 @@
          */
         private final int[] singleDoc = new int[1];
 
+        private int currentDoc = -1;
+
         /**
          * Creates a new <code>DescendantSelfAxisScorer</code>.
          *
@@ -447,53 +448,57 @@
             this.contextHits = new BitSet(reader.maxDoc());
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
-            collectContextHits();
-            int nextDoc = subScorer.nextDoc();
-            if (nextDoc == DocIdSetIterator.NO_MORE_DOCS || contextHits.isEmpty()) {
-                return false;
+        @Override
+        public int nextDoc() throws IOException {
+            if (currentDoc == NO_MORE_DOCS) {
+                return currentDoc;
             }
-            while (nextDoc != DocIdSetIterator.NO_MORE_DOCS) {
 
-                if (isValid(nextDoc)) {
-                    return true;
+            collectContextHits();
+            currentDoc = subScorer.nextDoc();
+            if (contextHits.isEmpty()) {
+                currentDoc = NO_MORE_DOCS;
-                }
+            }
+            while (currentDoc != NO_MORE_DOCS) {
+                if (isValid(currentDoc)) {
+                    return currentDoc;
+                }
 
                 // try next
-                nextDoc = subScorer.nextDoc();
+                currentDoc = subScorer.nextDoc();
             }
-            return false;
+            return currentDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
-            return subScorer.docID();
+        @Override
+        public int docID() {
+            return currentDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             return subScorer.score();
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
-            int docId = subScorer.nextDoc();
-            if (docId != DocIdSetIterator.NO_MORE_DOCS) {
-                collectContextHits();
-                return isValid(docId) || next();
+        @Override
+        public int advance(int target) throws IOException {
+            if (currentDoc == NO_MORE_DOCS) {
+                return currentDoc;
+            }
+
+            currentDoc = subScorer.nextDoc();
+            if (currentDoc == NO_MORE_DOCS) {
+                return NO_MORE_DOCS;
             } else {
-                return false;
+                collectContextHits();
+                if (isValid(currentDoc)) {
+                    return currentDoc;
-            }
+                }
+                else {
+                    return nextDoc();
-        }
+                }
+            }
+        }
 
         private void collectContextHits() throws IOException {
             if (!contextHitsCalculated) {
@@ -518,14 +523,6 @@
         }
 
         /**
-         * @throws UnsupportedOperationException this implementation always
-         *                                       throws an <code>UnsupportedOperationException</code>.
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
-        }
-
-        /**
          * Returns <code>true</code> if <code>doc</code> is a valid match from
          * the sub scorer against the context hits. The caller must ensure
          * that the context hits are calculated before this method is called!
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MultiScorer.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MultiScorer.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/MultiScorer.java	(revision )
@@ -16,7 +16,6 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
-import org.apache.lucene.search.DocIdSetIterator;
 import org.apache.lucene.search.Scorer;
 import org.apache.lucene.search.Similarity;
 
@@ -49,6 +48,8 @@
      */
     private boolean hasNext = true;
 
+    private int currentDoc = -1;
+
     /**
      * Creates a new <code>MultiScorer</code> that spans multiple
      * <code>scorers</code>.
@@ -63,13 +64,16 @@
         this.starts = starts;
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public boolean next() throws IOException {
+    @Override
+    public int nextDoc() throws IOException {
+        if (currentDoc == NO_MORE_DOCS) {
+            return currentDoc;
+        }
+
         while (hasNext) {
-            if (scorers[current].nextDoc() != DocIdSetIterator.NO_MORE_DOCS) {
-                return true;
+            if (scorers[current].nextDoc() != NO_MORE_DOCS) {
+                currentDoc = scorers[current].docID() + starts[current];
+                return currentDoc;
             } else if (++current < scorers.length) {
                 // advance to next scorer
             } else {
@@ -77,38 +81,41 @@
                 hasNext = false;
             }
         }
-        return hasNext;
+
+        currentDoc = NO_MORE_DOCS;
+        return currentDoc;
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public int doc() {
-        return scorers[current].docID() + starts[current];
+    @Override
+    public int docID() {
+        return currentDoc;
     }
 
-    /**
-     * {@inheritDoc}
-     */
+    @Override
     public float score() throws IOException {
         return scorers[current].score();
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public boolean skipTo(int target) throws IOException {
+    @Override
+    public int advance(int target) throws IOException {
+        if (currentDoc == NO_MORE_DOCS) {
+            return currentDoc;
+        }
+
         current = scorerIndex(target);
-        if (scorers[current].advance(target - starts[current]) != DocIdSetIterator.NO_MORE_DOCS) {
-            return true;
+        if (scorers[current].advance(target - starts[current]) != NO_MORE_DOCS) {
+            currentDoc = scorers[current].docID() + starts[current];
+            return currentDoc;
         } else {
             if (++current < scorers.length) {
                 // simply move to the next if there is any
-                return next();
+                currentDoc = nextDoc();
+                return currentDoc;
             } else {
                 // no more document
                 hasNext = false;
-                return hasNext;
+                currentDoc = NO_MORE_DOCS;
+                return currentDoc;
             }
         }
     }
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/RangeQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/RangeQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/RangeQuery.java	(revision )
@@ -16,14 +16,6 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.BitSet;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.Term;
 import org.apache.lucene.index.TermDocs;
@@ -39,8 +31,16 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.BitSet;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
 /**
- * Implements a variant of the lucene class {@link org.apache.lucene.search.RangeQuery}.
+ * Implements a variant of the lucene class {@link org.apache.lucene.search.RangeQuery}. // fixme lucene
  * This class does not rewrite to basic {@link org.apache.lucene.search.TermQuery}
  * but will calculate the matching documents itself. That way a
  * <code>TooManyClauses</code> can be avoided.
@@ -358,44 +358,42 @@
             hits = result;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateHits();
             nextDoc = hits.nextSetBit(nextDoc + 1);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateHits();
             nextDoc = hits.nextSetBit(target);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * Returns an empty Explanation object.
-         * @return an empty Explanation object.
-         */
-        public Explanation explain(int doc) {
-            return new Explanation();
+            return nextDoc;
         }
 
         /**
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DerefQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DerefQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/DerefQuery.java	(revision )
@@ -258,46 +258,42 @@
             this.hits = new BitSet(reader.maxDoc());
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             nextDoc = hits.nextSetBit(nextDoc + 1);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             nextDoc = hits.nextSetBit(target);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * {@inheritDoc}
-         *
-         * @throws UnsupportedOperationException this implementation always
-         *                                       throws an <code>UnsupportedOperationException</code>.
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
+            return nextDoc;
         }
 
         /**
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ParentAxisQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ParentAxisQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ParentAxisQuery.java	(revision )
@@ -16,12 +16,6 @@
  */
 package org.apache.jackrabbit.core.query.lucene;
 
-import java.io.IOException;
-import java.util.BitSet;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Set;
-
 import org.apache.jackrabbit.core.query.lucene.hits.AbstractHitCollector;
 import org.apache.jackrabbit.core.query.lucene.hits.Hits;
 import org.apache.jackrabbit.core.query.lucene.hits.ScorerHits;
@@ -34,6 +28,12 @@
 import org.apache.lucene.search.Similarity;
 import org.apache.lucene.search.Weight;
 
+import java.io.IOException;
+import java.util.BitSet;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
 /**
  * <code>ParentAxisQuery</code> selects the parent nodes of a context query.
  */
@@ -268,25 +268,26 @@
             this.hResolver = resolver;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateParent();
             nextDoc = hits.nextSetBit(nextDoc + 1);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             Float score = scores.get(nextDoc);
             if (score == null) {
@@ -295,23 +296,18 @@
             return score;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateParent();
             nextDoc = hits.nextSetBit(target);
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * {@inheritDoc}
-         *
-         * @throws UnsupportedOperationException this implementation always
-         *                                       throws an <code>UnsupportedOperationException</code>.
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
+            return nextDoc;
         }
 
         private void calculateParent() throws IOException {
Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ChildAxisQuery.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ChildAxisQuery.java	(revision 1060863)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/query/lucene/ChildAxisQuery.java	(revision )
@@ -387,52 +387,48 @@
             this.hResolver = hResolver;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean next() throws IOException {
+        @Override
+        public int nextDoc() throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             do {
                 nextDoc = hits.next();
             } while (nextDoc > -1 && !indexIsValid(nextDoc));
 
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
+            return nextDoc;
+        }
 
-        /**
-         * {@inheritDoc}
-         */
-        public int doc() {
+        @Override
+        public int docID() {
             return nextDoc;
         }
 
-        /**
-         * {@inheritDoc}
-         */
+        @Override
         public float score() throws IOException {
             return 1.0f;
         }
 
-        /**
-         * {@inheritDoc}
-         */
-        public boolean skipTo(int target) throws IOException {
+        @Override
+        public int advance(int target) throws IOException {
+            if (nextDoc == NO_MORE_DOCS) {
+                return nextDoc;
+            }
+
             calculateChildren();
             nextDoc = hits.skipTo(target);
             while (nextDoc > -1 && !indexIsValid(nextDoc)) {
-                next();
+                nextDoc();
             }
-            return nextDoc > -1;
+            if (nextDoc < 0) {
+                nextDoc = NO_MORE_DOCS;
-        }
+            }
-
-        /**
-         * {@inheritDoc}
-         *
-         * @throws UnsupportedOperationException this implementation always
-         *                                       throws an <code>UnsupportedOperationException</code>.
-         */
-        public Explanation explain(int doc) throws IOException {
-            throw new UnsupportedOperationException();
+            return nextDoc;
         }
 
         private void calculateChildren() throws IOException {