You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@lucene.apache.org by rm...@apache.org on 2011/01/05 00:38:31 UTC
svn commit: r1055243 -
/lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java
Author: rmuir
Date: Tue Jan 4 23:38:30 2011
New Revision: 1055243
URL: http://svn.apache.org/viewvc?rev=1055243&view=rev
Log:
LUCENE-2771: add MultiNorms (forgot to svn add)
Added:
lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java (with props)
Added: lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java?rev=1055243&view=auto
==============================================================================
--- lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java (added)
+++ lucene/dev/trunk/lucene/src/java/org/apache/lucene/index/MultiNorms.java Tue Jan 4 23:38:30 2011
@@ -0,0 +1,86 @@
+package org.apache.lucene.index;
+
+/**
+ * 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 java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.apache.lucene.search.Similarity;
+import org.apache.lucene.util.ReaderUtil;
+
+/**
+ * Exposes flex API, merged from flex API of sub-segments.
+ * This is useful when you're interacting with an {@link
+ * IndexReader} implementation that consists of sequential
+ * sub-readers (eg DirectoryReader or {@link
+ * MultiReader}).
+ *
+ * <p><b>NOTE</b>: for multi readers, you'll get better
+ * performance by gathering the sub readers using {@link
+ * ReaderUtil#gatherSubReaders} and then operate per-reader,
+ * instead of using this class.
+ *
+ * @lucene.experimental
+ */
+public class MultiNorms {
+ /**
+ * Warning: this is heavy! Do not use in a loop, or implement norms()
+ * in your own reader with this (you should likely cache the result).
+ */
+ public static byte[] norms(IndexReader r, String field) throws IOException {
+ final IndexReader[] subs = r.getSequentialSubReaders();
+ if (subs == null) {
+ // already an atomic reader
+ return r.norms(field);
+ } else if (subs.length == 0 || !r.hasNorms(field)) {
+ // no norms
+ return null;
+ } else if (subs.length == 1) {
+ return norms(subs[0], field);
+ } else {
+ // TODO: optimize more maybe
+ byte norms[] = new byte[r.maxDoc()];
+ final List<IndexReader> leaves = new ArrayList<IndexReader>();
+ ReaderUtil.gatherSubReaders(leaves, r);
+ int end = 0;
+ for (IndexReader leaf : leaves) {
+ int start = end;
+ leaf.norms(field, norms, start);
+ end += leaf.maxDoc();
+ }
+ return norms;
+ }
+ }
+
+ /**
+ * Warning: this is heavy! Do not use in a loop, or implement norms()
+ * in your own reader with this (you should likely cache the result).
+ */
+ public static void norms(IndexReader r, String field, byte[] bytes, int offset)
+ throws IOException {
+ // TODO: optimize more maybe
+ byte[] norms = norms(r, field);
+ if (norms == null) {
+ Arrays.fill(bytes, offset, bytes.length, Similarity.getDefault().encodeNormValue(1.0f));
+ } else {
+ System.arraycopy(norms, 0, bytes, offset, r.maxDoc());
+ }
+ }
+}