--- /dev/null
+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;
+import org.apache.lucene.util.LuceneTestCase;
+import org.junit.Test;
+
+public class MultiCollectorTest extends LuceneTestCase {
+
+ 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 {
+ MultiCollector.wrap(null, null);
+ fail("only null collectors 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 = MultiCollector.wrap(new DummyCollector(), null, new DummyCollector());
+ assertTrue(c instanceof MultiCollector);
+ assertTrue(c.acceptsDocsOutOfOrder());
+ c.collect(1);
+ c.setNextReader(null, 0);
+ c.setScorer(null);
+ }
+
+ @Test
+ public void testSingleCollector() throws Exception {
+ // Tests that if a single Collector is input, it is returned (and not MultiCollector).
+ DummyCollector dc = new DummyCollector();
+ assertSame(dc, MultiCollector.wrap(dc));
+ assertSame(dc, MultiCollector.wrap(dc, 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 = MultiCollector.wrap(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);
+ }
+
+ }
+
+}