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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.document;

/*
 * 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 org.apache.lucene.analysis.NumericTokenStream; // javadocs
import org.apache.lucene.index.FieldInfo.IndexOptions;
import org.apache.lucene.search.FieldCache; // javadocs
import org.apache.lucene.search.NumericRangeFilter; // javadocs
import org.apache.lucene.search.NumericRangeQuery; // javadocs
import org.apache.lucene.util.NumericUtils;

/**
 * 

* Field that indexes int values * for efficient range filtering and sorting. Here's an example usage: * *

 * document.add(new IntField(name, 6, Field.Store.NO));
 * 
* * For optimal performance, re-use the IntField and * {@link Document} instance for more than one document: * *
 *  IntField field = new IntField(name, 6, Field.Store.NO);
 *  Document document = new Document();
 *  document.add(field);
 * 
 *  for(all documents) {
 *    ...
 *    field.setIntValue(value)
 *    writer.addDocument(document);
 *    ...
 *  }
 * 
* * See also {@link LongField}, {@link FloatField}, {@link * DoubleField}. * *

To perform range querying or filtering against a * IntField, use {@link NumericRangeQuery} or {@link * NumericRangeFilter}. To sort according to a * IntField, use the normal numeric sort types, eg * {@link org.apache.lucene.search.SortField.Type#INT}. IntField * values can also be loaded directly from {@link FieldCache}.

* *

You may add the same field name as an IntField to * the same document more than once. Range querying and * filtering will be the logical OR of all values; so a range query * will hit all documents that have at least one value in * the range. However sort behavior is not defined. If you need to sort, * you should separately index a single-valued IntField.

* *

An IntField will consume somewhat more disk space * in the index than an ordinary single-valued field. * However, for a typical index that includes substantial * textual content per document, this increase will likely * be in the noise.

* *

Within Lucene, each numeric value is indexed as a * trie structure, where each term is logically * assigned to larger and larger pre-defined brackets (which * are simply lower-precision representations of the value). * The step size between each successive bracket is called the * precisionStep, measured in bits. Smaller * precisionStep values result in larger number * of brackets, which consumes more disk space in the index * but may result in faster range search performance. The * default value, 4, was selected for a reasonable tradeoff * of disk space consumption versus performance. You can * create a custom {@link FieldType} and invoke the {@link * FieldType#setNumericPrecisionStep} method if you'd * like to change the value. Note that you must also * specify a congruent value when creating {@link * NumericRangeQuery} or {@link NumericRangeFilter}. * For low cardinality fields larger precision steps are good. * If the cardinality is < 100, it is fair * to use {@link Integer#MAX_VALUE}, which produces one * term per value. * *

For more information on the internals of numeric trie * indexing, including the precisionStep * configuration, see {@link NumericRangeQuery}. The format of * indexed values is described in {@link NumericUtils}. * *

If you only need to sort by numeric value, and never * run range querying/filtering, you can index using a * precisionStep of {@link Integer#MAX_VALUE}. * This will minimize disk space consumed.

* *

More advanced users can instead use {@link * NumericTokenStream} directly, when indexing numbers. This * class is a wrapper around this token stream type for * easier, more intuitive usage.

* * @since 2.9 */ public final class IntField extends Field { /** * Type for an IntField that is not stored: * normalization factors, frequencies, and positions are omitted. */ public static final FieldType TYPE_NOT_STORED = new FieldType(); static { TYPE_NOT_STORED.setIndexed(true); TYPE_NOT_STORED.setTokenized(true); TYPE_NOT_STORED.setOmitNorms(true); TYPE_NOT_STORED.setIndexOptions(IndexOptions.DOCS_ONLY); TYPE_NOT_STORED.setNumericType(FieldType.NumericType.INT); TYPE_NOT_STORED.freeze(); } /** * Type for a stored IntField: * normalization factors, frequencies, and positions are omitted. */ public static final FieldType TYPE_STORED = new FieldType(); static { TYPE_STORED.setIndexed(true); TYPE_STORED.setTokenized(true); TYPE_STORED.setOmitNorms(true); TYPE_STORED.setIndexOptions(IndexOptions.DOCS_ONLY); TYPE_STORED.setNumericType(FieldType.NumericType.INT); TYPE_STORED.setStored(true); TYPE_STORED.freeze(); } /** Creates a stored or un-stored IntField with the provided value * and default precisionStep {@link * NumericUtils#PRECISION_STEP_DEFAULT} (4). * @param name field name * @param value 32-bit integer value * @param stored Store.YES if the content should also be stored * @throws IllegalArgumentException if the field name is null. */ public IntField(String name, int value, Store stored) { super(name, stored == Store.YES ? TYPE_STORED : TYPE_NOT_STORED); fieldsData = Integer.valueOf(value); } /** Expert: allows you to customize the {@link * FieldType}. * @param name field name * @param value 32-bit integer value * @param type customized field type: must have {@link FieldType#numericType()} * of {@link FieldType.NumericType#INT}. * @throws IllegalArgumentException if the field name or type is null, or * if the field type does not have a INT numericType() */ public IntField(String name, int value, FieldType type) { super(name, type); if (type.numericType() != FieldType.NumericType.INT) { throw new IllegalArgumentException("type.numericType() must be INT but got " + type.numericType()); } fieldsData = Integer.valueOf(value); } }




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