/*
* 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.common.params;
/**
* Parameters used for spellchecking
*
* @since solr 1.3
*/
public interface SpellingParams {
public static final String SPELLCHECK_PREFIX = "spellcheck.";
/**
* The name of the dictionary to be used for giving the suggestion for a
* request. The value for this parameter is configured in solrconfig.xml
*/
public static final String SPELLCHECK_DICT = SPELLCHECK_PREFIX + "dictionary";
/**
* The count of suggestions to return for each query term not in the index and/or dictionary.
* <p>
* If this parameter is absent in the request then only one suggestion is
* returned. If it is more than one then a maximum of given suggestions are
* returned for each token in the query.
*/
public static final String SPELLCHECK_COUNT = SPELLCHECK_PREFIX + "count";
/**
* The count of suggestions to return for each query term existing in the index and/or dictionary.
* <p>
* If this parameter is absent in the request then no suggestions are generated. This parameter allows
* for receiving alternative terms to use in context-sensitive spelling corrections.
*/
public static final String SPELLCHECK_ALTERNATIVE_TERM_COUNT = SPELLCHECK_PREFIX + "alternativeTermCount";
/**
* <p>
* The maximum number of hits the request can return in order to both
* generate spelling suggestions and set the "correctlySpelled" element to "false". This can be specified
* either as a whole number number of documents, or it can be expressed as a fractional percentage
* of documents returned by a chosen filter query. By default, the chosen filter is the most restrictive
* fq clause. This can be overridden with {@link SpellingParams#SPELLCHECK_MAX_RESULTS_FOR_SUGGEST_FQ} .
* </p>
* <p>
* If left unspecified, the default behavior will prevail. That is, "correctlySpelled" will be false and suggestions
* will be returned only if one or more of the query terms are absent from the dictionary and/or index. If set to zero,
* the "correctlySpelled" flag will be false only if the response returns zero hits. If set to a value greater than zero,
* suggestions will be returned even if hits are returned (up to the specified number). This number also will serve as
* the threshold in determining the value of "correctlySpelled". Specifying a value greater than zero is useful
* for creating "did-you-mean" suggestions for queries that return a low number of hits.
* </p>
*/
public static final String SPELLCHECK_MAX_RESULTS_FOR_SUGGEST = SPELLCHECK_PREFIX + "maxResultsForSuggest";
/**
*<p>
* To be used when {@link SpellingParams#SPELLCHECK_MAX_RESULTS_FOR_SUGGEST} is expressed as a fractional percentage.
* Specify a filter query whose result count is used to determine the maximum number of documents.
*</p>
*/
public static final String SPELLCHECK_MAX_RESULTS_FOR_SUGGEST_FQ = SPELLCHECK_MAX_RESULTS_FOR_SUGGEST + ".fq";
/**
* When this parameter is set to true and the misspelled word exists in the
* user field, only words that occur more frequently in the Solr field than
* the one given will be returned. The default value is false.
* <p>
* <b>This is applicable only for dictionaries built from Solr fields.</b>
*/
public static final String SPELLCHECK_ONLY_MORE_POPULAR = SPELLCHECK_PREFIX + "onlyMorePopular";
/**
* Whether to use the extended response format, which is more complicated but
* richer. Returns the document frequency for each suggestion and returns one
* suggestion block for each term in the query string. Default is false.
* <p>
* <b>This is applicable only for dictionaries built from Solr fields.</b>
*/
public static final String SPELLCHECK_EXTENDED_RESULTS = SPELLCHECK_PREFIX + "extendedResults";
/**
* Use the value for this parameter as the query to spell check.
* <p>
* This parameter is <b>optional</b>. If absent, then the q parameter is
* used.
*/
public static final String SPELLCHECK_Q = SPELLCHECK_PREFIX + "q";
/**
* Whether to build the index or not. Optional and false by default.
*/
public static final String SPELLCHECK_BUILD = SPELLCHECK_PREFIX + "build";
/**
* Whether to reload the index. Optional and false by default.
*/
public static final String SPELLCHECK_RELOAD = SPELLCHECK_PREFIX + "reload";
/**
* Take the top suggestion for each token and create a new query from it
*/
public static final String SPELLCHECK_COLLATE = SPELLCHECK_PREFIX + "collate";
/**
* <p>
* The maximum number of collations to return. Default=1. Ignored if "spellcheck.collate" is false.
* </p>
*/
public static final String SPELLCHECK_MAX_COLLATIONS = SPELLCHECK_PREFIX + "maxCollations";
/**
* <p>
* The maximum number of collations to test by querying against the index.
* When testing, the collation is substituted for the original query's "q" param. Any "qf"s are retained.
* If this is set to zero, does not test for hits before returning collations (returned collations may result in zero hits).
* Default=0. Ignored of "spellcheck.collate" is false.
* </p>
*/
public static final String SPELLCHECK_MAX_COLLATION_TRIES = SPELLCHECK_PREFIX + "maxCollationTries";
/**
* <p>
* The maximum number of word correction combinations to rank and evaluate prior to deciding which collation
* candidates to test against the index. This is a performance safety-net in cases a user enters a query with
* many misspelled words. The default is 10,000 combinations.
* </p>
*/
public static final String SPELLCHECK_MAX_COLLATION_EVALUATIONS = SPELLCHECK_PREFIX + "maxCollationEvaluations";
/**
* <p>
* For use with {@link SpellingParams#SPELLCHECK_MAX_COLLATION_TRIES} and
* {@link SpellingParams#SPELLCHECK_COLLATE_EXTENDED_RESULTS}.
* A performance optimization in cases where the exact number of hits a collation would return is not needed.
* Specify "0" to return the exact # of hits, otherwise give the maximum documents Lucene should collect
* with which to base an estimate. The higher the value the more likely the estimates will be accurate
* (at expense of performance).
* </p>
*
* <p>
* The default is 0 (report exact hit-counts) when {@link SpellingParams#SPELLCHECK_COLLATE_EXTENDED_RESULTS} is TRUE.
* When {@link SpellingParams#SPELLCHECK_COLLATE_EXTENDED_RESULTS} is FALSE, this optimization is always performed.
* </p>
*/
public static final String SPELLCHECK_COLLATE_MAX_COLLECT_DOCS = SPELLCHECK_PREFIX + "collateMaxCollectDocs";
/**
* <p>
* Whether to use the Extended Results Format for collations.
* Includes "before>after" pairs to easily allow clients to generate messages like "no results for PORK. did you mean POLK?"
* Also indicates the # of hits each collation will return on re-query. Default=false, which retains 1.4-compatible output.
* </p>
* <p>
* Note: that if {@link SpellingParams#SPELLCHECK_COLLATE_MAX_COLLECT_DOCS} is set to a value greater than 0,
* then the hit counts returned by this will be estimated.
* </p>
*/
public static final String SPELLCHECK_COLLATE_EXTENDED_RESULTS = SPELLCHECK_PREFIX + "collateExtendedResults";
/**
* <p>
* For use with {@link SpellingParams#SPELLCHECK_MAX_COLLATION_TRIES}, use this to override any original query parameters
* when issuing test queries. For instance, if the original query has "mm=1" but it is preferred to test collations
* with "mm=100%", then use "spellcheck.collateParam.mm=100%".
* </p>
*/
public static final String SPELLCHECK_COLLATE_PARAM_OVERRIDE = SPELLCHECK_PREFIX + "collateParam.";
/**
* Certain spelling implementations may allow for an accuracy setting.
*/
public static final String SPELLCHECK_ACCURACY = SPELLCHECK_PREFIX + "accuracy";
}