--- /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.analysis.MockAnalyzer;
+import org.apache.lucene.analysis.MockTokenizer;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.index.Term;
+import org.apache.lucene.index.RandomIndexWriter;
+import org.apache.lucene.store.Directory;
+import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util._TestUtil;
+
+/**
+ * Create an index with random unicode terms
+ * Generates random prefix queries, and validates against a simple impl.
+ */
+public class TestPrefixRandom extends LuceneTestCase {
+ private IndexSearcher searcher;
+ private IndexReader reader;
+ private Directory dir;
+
+ @Override
+ public void setUp() throws Exception {
+ super.setUp();
+ dir = newDirectory();
+ RandomIndexWriter writer = new RandomIndexWriter(random, dir,
+ newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random, MockTokenizer.KEYWORD, false))
+ .setMaxBufferedDocs(_TestUtil.nextInt(random, 50, 1000)));
+
+ Document doc = new Document();
+ Field bogus1 = newField("bogus", "", Field.Store.NO, Field.Index.NOT_ANALYZED_NO_NORMS);
+ Field field = newField("field", "", Field.Store.NO, Field.Index.NOT_ANALYZED);
+ Field bogus2 = newField("zbogus", "", Field.Store.NO, Field.Index.NOT_ANALYZED_NO_NORMS);
+ doc.add(field);
+ doc.add(bogus1);
+ doc.add(bogus2);
+
+ int num = atLeast(1000);
+
+ for (int i = 0; i < num; i++) {
+ field.setValue(_TestUtil.randomUnicodeString(random, 10));
+ bogus1.setValue(_TestUtil.randomUnicodeString(random, 10));
+ bogus2.setValue(_TestUtil.randomUnicodeString(random, 10));
+ writer.addDocument(doc);
+ }
+ reader = writer.getReader();
+ searcher = newSearcher(reader);
+ writer.close();
+ }
+
+ @Override
+ public void tearDown() throws Exception {
+ reader.close();
+ searcher.close();
+ dir.close();
+ super.tearDown();
+ }
+
+ /** a stupid prefix query that just blasts thru the terms */
+ private class DumbPrefixQuery extends MultiTermQuery {
+ private final Term prefix;
+
+ DumbPrefixQuery(Term term) {
+ super();
+ prefix = term;
+ }
+
+ @Override
+ protected FilteredTermEnum getEnum(IndexReader reader) throws IOException {
+ return new SimplePrefixTermEnum(reader, prefix);
+ }
+
+ private class SimplePrefixTermEnum extends FilteredTermEnum {
+ private final Term prefix;
+ private boolean endEnum;
+
+ private SimplePrefixTermEnum(IndexReader reader, Term prefix) throws IOException {
+ this.prefix = prefix;
+ setEnum(reader.terms(new Term(prefix.field(), "")));
+ }
+
+ @Override
+ protected boolean termCompare(Term term) {
+ if (term.field() == prefix.field()) {
+ return term.text().startsWith(prefix.text());
+ } else {
+ endEnum = true;
+ return false;
+ }
+ }
+
+ @Override
+ public float difference() {
+ return 1.0F;
+ }
+
+ @Override
+ protected boolean endEnum() {
+ return endEnum;
+ }
+ }
+
+ @Override
+ public String toString(String field) {
+ return field.toString() + ":" + prefix.toString();
+ }
+ }
+
+ /** test a bunch of random prefixes */
+ public void testPrefixes() throws Exception {
+ int num = atLeast(100);
+ for (int i = 0; i < num; i++)
+ assertSame(_TestUtil.randomUnicodeString(random, 5));
+ }
+
+ /** check that the # of hits is the same as from a very
+ * simple prefixquery implementation.
+ */
+ private void assertSame(String prefix) throws IOException {
+ PrefixQuery smart = new PrefixQuery(new Term("field", prefix));
+ DumbPrefixQuery dumb = new DumbPrefixQuery(new Term("field", prefix));
+
+ TopDocs smartDocs = searcher.search(smart, 25);
+ TopDocs dumbDocs = searcher.search(dumb, 25);
+ CheckHits.checkEqual(smart, smartDocs.scoreDocs, dumbDocs.scoreDocs);
+ }
+}