/*
* 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.
*/
package org.apache.lucene.analysis.tokenattributes;
import org.apache.lucene.util.Attribute;
import org.apache.lucene.util.BytesRef;
/**
* This attribute is requested by TermsHashPerField to index the contents.
* This attribute can be used to customize the final byte[] encoding of terms.
* <p>
* Consumers of this attribute call {@link #getBytesRef()} for each term. Example:
* <pre class="prettyprint">
* final TermToBytesRefAttribute termAtt = tokenStream.getAttribute(TermToBytesRefAttribute.class);
*
* while (tokenStream.incrementToken() {
* final BytesRef bytes = termAtt.getBytesRef();
*
* if (isInteresting(bytes)) {
*
* // because the bytes are reused by the attribute (like CharTermAttribute's char[] buffer),
* // you should make a copy if you need persistent access to the bytes, otherwise they will
* // be rewritten across calls to incrementToken()
*
* doSomethingWith(BytesRef.deepCopyOf(bytes));
* }
* }
* ...
* </pre>
* @lucene.internal This is a very expert and internal API, please use
* {@link CharTermAttribute} and its implementation for UTF-8 terms; to
* index binary terms, use {@link BytesTermAttribute} and its implementation.
*/
public interface TermToBytesRefAttribute extends Attribute {
/**
* Retrieve this attribute's BytesRef. The bytes are updated from the current term.
* The implementation may return a new instance or keep the previous one.
* @return a BytesRef to be indexed (only stays valid until token stream gets incremented)
*/
public BytesRef getBytesRef();
}