| 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 org.apache.lucene.index.FieldInfo.IndexOptions; |
| import org.apache.lucene.search.DocIdSetIterator; |
| import org.apache.lucene.util.AttributeSource; |
| import org.apache.lucene.util.Bits; // javadocs |
| |
| /** Iterates through the documents and term freqs. |
| * NOTE: you must first call {@link #nextDoc} before using |
| * any of the per-doc methods. */ |
| public abstract class DocsEnum extends DocIdSetIterator { |
| |
| /** |
| * Flag to pass to {@link TermsEnum#docs(Bits,DocsEnum,int)} if you don't |
| * require term frequencies in the returned enum. When passed to |
| * {@link TermsEnum#docsAndPositions(Bits,DocsAndPositionsEnum,int)} means |
| * that no offsets and payloads will be returned. |
| */ |
| public static final int FLAG_NONE = 0x0; |
| |
| /** Flag to pass to {@link TermsEnum#docs(Bits,DocsEnum,int)} |
| * if you require term frequencies in the returned enum. */ |
| public static final int FLAG_FREQS = 0x1; |
| |
| private AttributeSource atts = null; |
| |
| /** Sole constructor. (For invocation by subclass |
| * constructors, typically implicit.) */ |
| protected DocsEnum() { |
| } |
| |
| /** |
| * Returns term frequency in the current document, or 1 if the field was |
| * indexed with {@link IndexOptions#DOCS_ONLY}. Do not call this before |
| * {@link #nextDoc} is first called, nor after {@link #nextDoc} returns |
| * {@link DocIdSetIterator#NO_MORE_DOCS}. |
| * |
| * <p> |
| * <b>NOTE:</b> if the {@link DocsEnum} was obtain with {@link #FLAG_NONE}, |
| * the result of this method is undefined. |
| */ |
| public abstract int freq() throws IOException; |
| |
| /** Returns the related attributes. */ |
| public AttributeSource attributes() { |
| if (atts == null) atts = new AttributeSource(); |
| return atts; |
| } |
| } |