Index: CHANGES.txt
===================================================================
--- CHANGES.txt (revision 995054)
+++ CHANGES.txt (working copy)
@@ -371,6 +371,9 @@
to gather the hit-count per sub-clause and per document while a
search is running. (Simon Willnauer, Mike McCandless)
+* LUCENE-2636: Added ChainingCollector which allows chaining several Collectors
+ together and be passed to IndexSearcher.search methods. (Shai Erera)
+
Optimizations
* LUCENE-2494: Use CompletionService in ParallelMultiSearcher instead of
Index: src/test/org/apache/lucene/search/ChainingCollectorTest.java
===================================================================
--- src/test/org/apache/lucene/search/ChainingCollectorTest.java (revision 0)
+++ src/test/org/apache/lucene/search/ChainingCollectorTest.java (revision 0)
@@ -0,0 +1,103 @@
+package org.apache.lucene.search;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+
+import static org.junit.Assert.*;
+
+import java.io.IOException;
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.search.Collector;
+import org.apache.lucene.search.Scorer;
+import org.apache.lucene.util.LuceneTestCaseJ4;
+import org.junit.Test;
+
+public class ChainingCollectorTest extends LuceneTestCaseJ4 {
+
+ private static class DummyCollector extends Collector {
+
+ boolean acceptsDocsOutOfOrderCalled = false;
+ boolean collectCalled = false;
+ boolean setNextReaderCalled = false;
+ boolean setScorerCalled = false;
+
+ @Override
+ public boolean acceptsDocsOutOfOrder() {
+ acceptsDocsOutOfOrderCalled = true;
+ return true;
+ }
+
+ @Override
+ public void collect(int doc) throws IOException {
+ collectCalled = true;
+ }
+
+ @Override
+ public void setNextReader(IndexReader reader, int docBase) throws IOException {
+ setNextReaderCalled = true;
+ }
+
+ @Override
+ public void setScorer(Scorer scorer) throws IOException {
+ setScorerCalled = true;
+ }
+
+ }
+
+ @Test
+ public void testNullCollectors() throws Exception {
+ // Tests that the collector rejects all null collectors.
+ try {
+ new ChainingCollector(null, null);
+ fail("all collectors null should not be supported");
+ } catch (IllegalArgumentException e) {
+ // expected
+ }
+
+ // Tests that the collector handles some null collectors well. If it
+ // doesn't, an NPE would be thrown.
+ Collector c = new ChainingCollector(new DummyCollector(), null, new DummyCollector());
+ assertTrue(c.acceptsDocsOutOfOrder());
+ c.collect(1);
+ c.setNextReader(null, 0);
+ c.setScorer(null);
+ }
+
+ @Test
+ public void testCollector() throws Exception {
+ // Tests that the collector delegates calls to input collectors properly.
+
+ // Tests that the collector handles some null collectors well. If it
+ // doesn't, an NPE would be thrown.
+ DummyCollector[] dcs = new DummyCollector[] { new DummyCollector(), new DummyCollector() };
+ Collector c = new ChainingCollector(dcs);
+ assertTrue(c.acceptsDocsOutOfOrder());
+ c.collect(1);
+ c.setNextReader(null, 0);
+ c.setScorer(null);
+
+ for (DummyCollector dc : dcs) {
+ assertTrue(dc.acceptsDocsOutOfOrderCalled);
+ assertTrue(dc.collectCalled);
+ assertTrue(dc.setNextReaderCalled);
+ assertTrue(dc.setScorerCalled);
+ }
+
+ }
+
+}
Property changes on: src/test/org/apache/lucene/search/ChainingCollectorTest.java
___________________________________________________________________
Added: svn:keywords
+ Date Author Id Revision HeadURL
Added: svn:eol-style
+ native
Index: src/java/org/apache/lucene/search/ChainingCollector.java
===================================================================
--- src/java/org/apache/lucene/search/ChainingCollector.java (revision 0)
+++ src/java/org/apache/lucene/search/ChainingCollector.java (revision 0)
@@ -0,0 +1,100 @@
+package org.apache.lucene.search;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+
+import java.io.IOException;
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.search.Collector;
+import org.apache.lucene.search.Scorer;
+
+/**
+ * A {@link Collector} which allows chaining several {@link Collector}s in order
+ * to process the matching documents emitted to {@link #collect(int)}. This
+ * collector accepts a list of {@link Collector}s in its constructor, allowing
+ * for some of them to be null. It optimizes away those
+ * null collectors, so that they are not acessed during collection
+ * time.
+ *
+ * NOTE: if all the collectors passed to the constructor are null, then
+ * {@link IllegalArgumentException} is thrown - it is useless to run the search
+ * with 0 collectors.
+ */
+public class ChainingCollector extends Collector {
+
+ private final Collector[] collectors;
+
+ public ChainingCollector(Collector... collectors) {
+ // For the user's convenience, we allow null collectors to be passed.
+ // However, to improve performance, these null collectors are found
+ // and dropped from the array we save for actual collection time.
+ int n = 0;
+ for (Collector c : collectors) {
+ if (c != null) {
+ n++;
+ }
+ }
+
+ if (n == 0) {
+ throw new IllegalArgumentException("At least 1 collector must not be null");
+ } else if (n == collectors.length) {
+ // No null collectors, can use the given list as is.
+ this.collectors = collectors;
+ } else {
+ this.collectors = new Collector[n];
+ n = 0;
+ for (Collector c : collectors) {
+ if (c != null) {
+ this.collectors[n++] = c;
+ }
+ }
+ }
+ }
+
+ @Override
+ public boolean acceptsDocsOutOfOrder() {
+ for (Collector c : collectors) {
+ if (!c.acceptsDocsOutOfOrder()) {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ @Override
+ public void collect(int doc) throws IOException {
+ for (Collector c : collectors) {
+ c.collect(doc);
+ }
+ }
+
+ @Override
+ public void setNextReader(IndexReader reader, int o) throws IOException {
+ for (Collector c : collectors) {
+ c.setNextReader(reader, o);
+ }
+ }
+
+ @Override
+ public void setScorer(Scorer s) throws IOException {
+ for (Collector c : collectors) {
+ c.setScorer(s);
+ }
+ }
+
+}
Property changes on: src/java/org/apache/lucene/search/ChainingCollector.java
___________________________________________________________________
Added: svn:keywords
+ Date Author Id Revision HeadURL
Added: svn:eol-style
+ native