LUCENE-1427: speed up QueryWrapperFilter by not computing scores nor an intermediate OpenBitSet

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@709459 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -12,6 +12,9 @@ API Changes
    Yet, it will give us the possibility to try out different consumers in
    in the chain. (Michael Busch)
 
+2. LUCENE-1427: DocIdSet.iterator() is now allowed to throw
+   IOException.  (Paul Elschot, Mike McCandless)
+
 Bug fixes
 
 1. LUCENE-1415: MultiPhraseQuery has incorrect hashCode() and equals()
@@ -38,6 +41,12 @@ New features
 
 Optimizations
 
+ 1. LUCENE-1427: Fixed QueryWrapperFilter to not waste time computing
+    scores of the query, since they are just discarded.  Also, made it
+    more efficient (single pass) by not creating & populating an
+    intermediate OpenBitSet (Paul Elschot, Mike McCandless)
+
+
 Documentation
 
 Build

src/java/org/apache/lucene/search/DocIdSet.java

@@ -17,11 +17,12 @@ package org.apache.lucene.search;
  * limitations under the License.
  */
 
+import java.io.IOException;
 
 /**
  * A DocIdSet contains a set of doc ids. Implementing classes must provide
  * a {@link DocIdSetIterator} to access the set. 
  */
 public abstract class DocIdSet {
-	public abstract DocIdSetIterator iterator();
+	public abstract DocIdSetIterator iterator() throws IOException;
 }

src/java/org/apache/lucene/search/QueryWrapperFilter.java

@@ -59,15 +59,13 @@ public class QueryWrapperFilter extends Filter {
     return bits;
   }
   
-  public DocIdSet getDocIdSet(IndexReader reader) throws IOException {
-    final OpenBitSet bits = new OpenBitSet(reader.maxDoc());
-
-    new IndexSearcher(reader).search(query, new HitCollector() {
-      public final void collect(int doc, float score) {
-        bits.set(doc);  // set bit for hit
+  public DocIdSet getDocIdSet(final IndexReader reader) throws IOException {
+    final Weight weight = query.weight(new IndexSearcher(reader));
+    return new DocIdSet() {
+      public DocIdSetIterator iterator() throws IOException {
+        return weight.scorer(reader);
       }
-    });
-    return bits;
+    };
   }
 
   public String toString() {