org.apache.lucene.codecs.package-info Maven / Gradle / Ivy
/*
* 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.
*/
/**
* Codecs API: API for customization of the encoding and structure of the index.
*
*
* The Codec API allows you to customise the way the following pieces of index information are stored:
*
* - Postings lists - see {@link org.apache.lucene.codecs.PostingsFormat}
* - DocValues - see {@link org.apache.lucene.codecs.DocValuesFormat}
* - Stored fields - see {@link org.apache.lucene.codecs.StoredFieldsFormat}
* - Term vectors - see {@link org.apache.lucene.codecs.TermVectorsFormat}
* - FieldInfos - see {@link org.apache.lucene.codecs.FieldInfosFormat}
* - SegmentInfo - see {@link org.apache.lucene.codecs.SegmentInfoFormat}
* - Norms - see {@link org.apache.lucene.codecs.NormsFormat}
* - Live documents - see {@link org.apache.lucene.codecs.LiveDocsFormat}
*
*
* For some concrete implementations beyond Lucene's official index format, see
* the Codecs module.
*
*
* Codecs are identified by name through the Java Service Provider Interface. To create your own codec, extend
* {@link org.apache.lucene.codecs.Codec} and pass the new codec's name to the super() constructor:
*
* public class MyCodec extends Codec {
*
* public MyCodec() {
* super("MyCodecName");
* }
*
* ...
* }
*
* You will need to register the Codec class so that the {@link java.util.ServiceLoader ServiceLoader} can find it, by including a
* META-INF/services/org.apache.lucene.codecs.Codec file on your classpath that contains the package-qualified
* name of your codec.
*
*
* If you just want to customise the {@link org.apache.lucene.codecs.PostingsFormat}, or use different postings
* formats for different fields, then you can register your custom postings format in the same way (in
* META-INF/services/org.apache.lucene.codecs.PostingsFormat), and then extend the default
* codec and override
* {@code org.apache.lucene.codecs.luceneMN.LuceneMNCodec#getPostingsFormatForField(String)} to return your custom
* postings format.
*
*
* Similarly, if you just want to customise the {@link org.apache.lucene.codecs.DocValuesFormat} per-field, have
* a look at {@code LuceneMNCodec.getDocValuesFormatForField(String)}.
*
*/
package org.apache.lucene.codecs;