Java tutorial
/* * 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.search; import org.apache.solr.common.params.SolrParams; import org.apache.solr.request.SolrQueryRequest; /** * Create a dismax query from the input value. * <br>localParams are checked before global request params. * <br>Example: <code>{!dismax qf='myfield mytitle^2'}foo</code> creates a dismax query across * across myfield and mytitle, with a higher weight on mytitle. * * <p> * A Generic query plugin designed to be given a simple query expression * from a user, which it will then query against a variety of * pre-configured fields, in a variety of ways, using BooleanQueries, * DisjunctionMaxQueries, and PhraseQueries. * </p> * * <p> * All of the following options may be configured for this plugin * in the solrconfig as defaults, and may be overriden as request parameters * </p> * * <ul> * <li>q.alt - An alternate query to be used in cases where the main * query (q) is not specified (or blank). This query should * be expressed in the Standard SolrQueryParser syntax (you * can use <code>q.alt=*:*</code> to denote that all documents * should be returned when no query is specified) * </li> * <li>tie - (Tie breaker) float value to use as tiebreaker in * DisjunctionMaxQueries (should be something much less than 1) * </li> * <li> qf - (Query Fields) fields and boosts to use when building * DisjunctionMaxQueries from the users query. Format is: * "<code>fieldA^1.0 fieldB^2.2</code>". * This param can be specified multiple times, and the fields * are additive. * </li> * <li> mm - (Minimum Match) this supports a wide variety of * complex expressions. * read {@link org.apache.solr.util.SolrPluginUtils#setMinShouldMatch SolrPluginUtils.setMinShouldMatch} and <a href="{@docRoot}/org/apache/solr/util/doc-files/min-should-match.html">mm expression format</a> for details. * </li> * <li> pf - (Phrase Fields) fields/boosts to make phrase queries out * of, to boost the users query for exact matches on the specified fields. * Format is: "<code>fieldA^1.0 fieldB^2.2</code>". * This param can be specified multiple times, and the fields * are additive. * </li> * <li> ps - (Phrase Slop) amount of slop on phrase queries built for pf * fields. * </li> * <li> qs - (Query Slop) amount of slop on phrase queries explicitly * specified in the "q" for qf fields. * </li> * <li> bq - (Boost Query) a raw lucene query that will be included in the * users query to influence the score. If this is a BooleanQuery * with a default boost (1.0f), then the individual clauses will be * added directly to the main query. Otherwise, the query will be * included as is. * This param can be specified multiple times, and the boosts are * are additive. NOTE: the behaviour listed above is only in effect * if a single <code>bq</code> paramter is specified. Hence you can * disable it by specifying an additional, blank, <code>bq</code> * parameter. * </li> * <li> bf - (Boost Functions) functions (with optional boosts) that will be * included in the users query to influence the score. * Format is: "<code>funcA(arg1,arg2)^1.2 * funcB(arg3,arg4)^2.2</code>". NOTE: Whitespace is not allowed * in the function arguments. * This param can be specified multiple times, and the functions * are additive. * </li> * <li> fq - (Filter Query) a raw lucene query that can be used * to restrict the super set of products we are interested in - more * efficient then using bq, but doesn't influence score. * This param can be specified multiple times, and the filters * are additive. * </li> * </ul> * * <p> * The following options are only available as request params... * </p> * * <ul> * <li> q - (Query) the raw unparsed, unescaped, query from the user. * </li> * <li>sort - (Order By) list of fields and direction to sort on. * </li> * </ul> * */ public class DisMaxQParserPlugin extends QParserPlugin { public static final String NAME = "dismax"; @Override public QParser createParser(String qstr, SolrParams localParams, SolrParams params, SolrQueryRequest req) { return new DisMaxQParser(qstr, localParams, params, req); } }