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/*
* 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.solr.legacy;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.FloatPoint;
import org.apache.lucene.index.IndexOptions;
/**
* Field that indexes float values for efficient range filtering and sorting. Here's an
* example usage:
*
*
* document.add(new LegacyFloatField(name, 6.0F, Field.Store.NO));
*
*
* For optimal performance, re-use the LegacyFloatField and {@link Document} instance
* for more than one document:
*
*
* LegacyFloatField field = new LegacyFloatField(name, 0.0F, Field.Store.NO);
* Document document = new Document();
* document.add(field);
*
* for(all documents) {
* ...
* field.setFloatValue(value)
* writer.addDocument(document);
* ...
* }
*
*
* See also {@link LegacyIntField}, {@link LegacyLongField}, {@link LegacyDoubleField}.
*
* To perform range querying or filtering against a LegacyFloatField, use {@link
* org.apache.solr.legacy.LegacyNumericRangeQuery}. To sort according to a LegacyFloatField
* , use the normal numeric sort types, eg {@link
* org.apache.lucene.search.SortField.Type#FLOAT}. LegacyFloatField values can also be
* loaded directly from {@link org.apache.lucene.index.LeafReader#getNumericDocValues}.
*
*
You may add the same field name as an LegacyFloatField 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 LegacyFloatField
* .
*
*
A LegacyFloatField 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, 8, was selected for a reasonable tradeoff of disk
* space consumption versus performance. You can create a custom {@link LegacyFieldType} and invoke
* the {@link LegacyFieldType#setNumericPrecisionStep} method if you'd like to change the value.
* Note that you must also specify a congruent value when creating {@link
* org.apache.solr.legacy.LegacyNumericRangeQuery}. 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 org.apache.solr.legacy.LegacyNumericRangeQuery}. The format of indexed
* values is described in {@link org.apache.solr.legacy.LegacyNumericUtils}.
*
*
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 org.apache.solr.legacy.LegacyNumericTokenStream}
* directly, when indexing numbers. This class is a wrapper around this token stream type for
* easier, more intuitive usage.
*
* @deprecated Please use {@link FloatPoint} instead
* @since 2.9
*/
@Deprecated
public final class LegacyFloatField extends LegacyField {
/**
* Type for a LegacyFloatField that is not stored: normalization factors, frequencies, and
* positions are omitted.
*/
public static final LegacyFieldType TYPE_NOT_STORED = new LegacyFieldType();
static {
TYPE_NOT_STORED.setTokenized(true);
TYPE_NOT_STORED.setOmitNorms(true);
TYPE_NOT_STORED.setIndexOptions(IndexOptions.DOCS);
TYPE_NOT_STORED.setNumericType(LegacyNumericType.FLOAT);
TYPE_NOT_STORED.setNumericPrecisionStep(LegacyNumericUtils.PRECISION_STEP_DEFAULT_32);
TYPE_NOT_STORED.freeze();
}
/**
* Type for a stored LegacyFloatField: normalization factors, frequencies, and positions are
* omitted.
*/
public static final LegacyFieldType TYPE_STORED = new LegacyFieldType();
static {
TYPE_STORED.setTokenized(true);
TYPE_STORED.setOmitNorms(true);
TYPE_STORED.setIndexOptions(IndexOptions.DOCS);
TYPE_STORED.setNumericType(LegacyNumericType.FLOAT);
TYPE_STORED.setNumericPrecisionStep(LegacyNumericUtils.PRECISION_STEP_DEFAULT_32);
TYPE_STORED.setStored(true);
TYPE_STORED.freeze();
}
/**
* Creates a stored or un-stored LegacyFloatField with the provided value and default
* precisionStep {@link
* org.apache.solr.legacy.LegacyNumericUtils#PRECISION_STEP_DEFAULT_32} (8).
*
* @param name field name
* @param value 32-bit double value
* @param stored Store.YES if the content should also be stored
* @throws IllegalArgumentException if the field name is null.
*/
public LegacyFloatField(String name, float value, Store stored) {
super(name, stored == Store.YES ? TYPE_STORED : TYPE_NOT_STORED);
fieldsData = Float.valueOf(value);
}
/**
* Expert: allows you to customize the {@link LegacyFieldType}.
*
* @param name field name
* @param value 32-bit float value
* @param type customized field type: must have {@link LegacyFieldType#numericType()} of {@link
* LegacyNumericType#FLOAT}.
* @throws IllegalArgumentException if the field name or type is null, or if the field type does
* not have a FLOAT numericType()
*/
public LegacyFloatField(String name, float value, LegacyFieldType type) {
super(name, type);
if (type.numericType() != LegacyNumericType.FLOAT) {
throw new IllegalArgumentException(
"type.numericType() must be FLOAT but got " + type.numericType());
}
fieldsData = Float.valueOf(value);
}
}