Index: src/test/org/apache/lucene/search/TestTopDocsCollector.java
===================================================================
--- src/test/org/apache/lucene/search/TestTopDocsCollector.java	(revision 962932)
+++ src/test/org/apache/lucene/search/TestTopDocsCollector.java	(working copy)
@@ -30,7 +30,7 @@
 
 public class TestTopDocsCollector extends LuceneTestCase {
 
-  private static final class MyTopsDocCollector extends TopDocsCollector {
+  private static final class MyTopsDocCollector extends TopDocsCollector<ScoreDoc> {
 
     private int idx = 0;
     private int base = 0;
@@ -207,4 +207,46 @@
     }
   }
   
+  public void testSubclassWithoutPQ() throws IOException {
+    final TopDocs mtd = new TopDocs( 77, new ScoreDoc[0] );
+    
+    // this is a completely bogus TDC just showing that PQ can be null and we can override
+    // methods that were previously final
+    TopDocsCollector<ScoreDoc> tdc = new TopDocsCollector<ScoreDoc>(null) {
+      @Override
+      public boolean acceptsDocsOutOfOrder() {
+        return true;
+      }
+      @Override
+      public void collect(int doc) throws IOException {
+        ++totalHits;
+      }
+      @Override
+      public void setNextReader(IndexReader reader, int docBase) throws IOException {
+      }
+      @Override
+      public void setScorer(Scorer scorer) throws IOException {
+      }
+      @Override
+      public TopDocs topDocs() {
+        return mtd;
+      }
+      @Override
+      public TopDocs topDocs(int start) {
+        return mtd;
+      }
+      @Override
+      public TopDocs topDocs(int start, int end) {
+        return mtd;
+      }
+    };
+    
+    Query q = new MatchAllDocsQuery();
+    IndexSearcher searcher = new IndexSearcher(dir, true);
+    searcher.search(q, tdc);
+    searcher.close();
+    assertEquals(30, tdc.getTotalHits());
+    assertEquals(77, tdc.topDocs().totalHits);
+  }
+  
 }
Index: src/java/org/apache/lucene/search/TopDocsCollector.java
===================================================================
--- src/java/org/apache/lucene/search/TopDocsCollector.java	(revision 962932)
+++ src/java/org/apache/lucene/search/TopDocsCollector.java	(working copy)
@@ -25,8 +25,10 @@
  * collector allows easy extension by providing a single constructor which
  * accepts a {@link PriorityQueue} as well as protected members for that
  * priority queue and a counter of the number of total hits.<br>
- * Extending classes can override {@link #topDocs(int, int)} and
- * {@link #getTotalHits()} in order to provide their own implementation.
+ * Most extending classes can override {@link #newTopDocs(ScoreDoc[], int)} and
+ * {@link #populateResults(ScoreDoc[], int)} in order to provide their own
+ * implementation. Subclasses may completely change behavior by overridding the
+ * various topDocs() methods etc.
  */
 public abstract class TopDocsCollector<T extends ScoreDoc> extends Collector {
 
@@ -45,12 +47,17 @@
   /** The total number of documents that the collector encountered. */
   protected int totalHits;
   
+  /**
+   * construct with a {@link PriorityQueue}, may be null. If you plan to implement
+   * without using a pq, you must override ALL public methods.
+   * @param pq
+   */
   protected TopDocsCollector(PriorityQueue<T> pq) {
     this.pq = pq;
   }
   
   /**
-   * Populates the results array with the ScoreDoc instaces. This can be
+   * Populates the results array with the ScoreDoc instances. This can be
    * overridden in case a different ScoreDoc type should be returned.
    */
   protected void populateResults(ScoreDoc[] results, int howMany) {
@@ -75,7 +82,7 @@
   }
   
   /** Returns the top docs that were collected by this collector. */
-  public final TopDocs topDocs() {
+  public TopDocs topDocs() {
     // In case pq was populated with sentinel values, there might be less
     // results than pq.size(). Therefore return all results until either
     // pq.size() or totalHits.
@@ -94,7 +101,7 @@
    * with the returned {@link TopDocs} object, which will contain all the
    * results this search execution collected.
    */
-  public final TopDocs topDocs(int start) {
+  public TopDocs topDocs(int start) {
     // In case pq was populated with sentinel values, there might be less
     // results than pq.size(). Therefore return all results until either
     // pq.size() or totalHits.
@@ -115,7 +122,7 @@
    * returned {@link TopDocs} object, which will contain all the results this
    * search execution collected.
    */
-  public final TopDocs topDocs(int start, int howMany) {
+  public TopDocs topDocs(int start, int howMany) {
     
     // In case pq was populated with sentinel values, there might be less
     // results than pq.size(). Therefore return all results until either