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/*
 * COPIED FROM APACHE LUCENE 4.7.2
 *
 * Git URL: [email protected]:apache/lucene.git, tag: releases/lucene-solr/4.7.2, path: lucene/core/src/java
 *
 * (see https://issues.apache.org/jira/browse/OAK-10786 for details)
 */

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.document.Document;
import org.apache.lucene.document.DocumentStoredFieldVisitor;

/**
 * Expert: provides a low-level means of accessing the stored field
 * values in an index.  See {@link IndexReader#document(int,
 * StoredFieldVisitor)}.
 *
 * 

NOTE: a {@code StoredFieldVisitor} implementation * should not try to load or visit other stored documents in * the same reader because the implementation of stored * fields for most codecs is not reeentrant and you will see * strange exceptions as a result. * *

See {@link DocumentStoredFieldVisitor}, which is a * StoredFieldVisitor that builds the * {@link Document} containing all stored fields. This is * used by {@link IndexReader#document(int)}. * * @lucene.experimental */ public abstract class StoredFieldVisitor { /** Sole constructor. (For invocation by subclass * constructors, typically implicit.) */ protected StoredFieldVisitor() { } /** Process a binary field. * @param value newly allocated byte array with the binary contents. */ public void binaryField(FieldInfo fieldInfo, byte[] value) throws IOException { } /** Process a string field */ public void stringField(FieldInfo fieldInfo, String value) throws IOException { } /** Process a int numeric field. */ public void intField(FieldInfo fieldInfo, int value) throws IOException { } /** Process a long numeric field. */ public void longField(FieldInfo fieldInfo, long value) throws IOException { } /** Process a float numeric field. */ public void floatField(FieldInfo fieldInfo, float value) throws IOException { } /** Process a double numeric field. */ public void doubleField(FieldInfo fieldInfo, double value) throws IOException { } /** * Hook before processing a field. * Before a field is processed, this method is invoked so that * subclasses can return a {@link Status} representing whether * they need that particular field or not, or to stop processing * entirely. */ public abstract Status needsField(FieldInfo fieldInfo) throws IOException; /** * Enumeration of possible return values for {@link #needsField}. */ public static enum Status { /** YES: the field should be visited. */ YES, /** NO: don't visit this field, but continue processing fields for this document. */ NO, /** STOP: don't visit this field and stop processing any other fields for this document. */ STOP } }





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