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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 java.io.Reader;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.search.similarities.DefaultSimilarity; // javadocs
import org.apache.lucene.search.similarities.Similarity; // javadocs
import org.apache.lucene.util.BytesRef;

// TODO: how to handle versioning here...?

// TODO: we need to break out separate StoredField...

/** Represents a single field for indexing.  IndexWriter
 *  consumes Iterable<IndexableField> as a document.
 *
 *  @lucene.experimental */

public interface IndexableField {

  /** Field name */
  public String name();

  /** {@link IndexableFieldType} describing the properties
   * of this field. */
  public IndexableFieldType fieldType();
  
  /** 
   * Returns the field's index-time boost.
   * 

* Only fields can have an index-time boost, if you want to simulate * a "document boost", then you must pre-multiply it across all the * relevant fields yourself. *

The boost is used to compute the norm factor for the field. By * default, in the {@link Similarity#computeNorm(FieldInvertState)} method, * the boost value is multiplied by the length normalization factor and then * rounded by {@link DefaultSimilarity#encodeNormValue(float)} before it is stored in the * index. One should attempt to ensure that this product does not overflow * the range of that encoding. *

* It is illegal to return a boost other than 1.0f for a field that is not * indexed ({@link IndexableFieldType#indexed()} is false) or omits normalization values * ({@link IndexableFieldType#omitNorms()} returns true). * * @see Similarity#computeNorm(FieldInvertState) * @see DefaultSimilarity#encodeNormValue(float) */ public float boost(); /** Non-null if this field has a binary value */ public BytesRef binaryValue(); /** Non-null if this field has a string value */ public String stringValue(); /** Non-null if this field has a Reader value */ public Reader readerValue(); /** Non-null if this field has a numeric value */ public Number numericValue(); /** * Creates the TokenStream used for indexing this field. If appropriate, * implementations should use the given Analyzer to create the TokenStreams. * * @param analyzer Analyzer that should be used to create the TokenStreams from * @return TokenStream value for indexing the document. Should always return * a non-null value if the field is to be indexed * @throws IOException Can be thrown while creating the TokenStream */ public TokenStream tokenStream(Analyzer analyzer) throws IOException; }





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