lucene-java-3.5.0/lucene/contrib/xml-query-parser/src/java/org/apache/lucene/xmlparser/builders/BooleanQueryBuilder.java

   1 /*
   2  * Created on 25-Jan-2006
   3  */
   4 package org.apache.lucene.xmlparser.builders;
   5
   6 import org.apache.lucene.search.BooleanClause;
   7 import org.apache.lucene.search.BooleanQuery;
   8 import org.apache.lucene.search.Query;
   9 import org.apache.lucene.xmlparser.DOMUtils;
  10 import org.apache.lucene.xmlparser.ParserException;
  11 import org.apache.lucene.xmlparser.QueryBuilder;
  12 import org.w3c.dom.Element;
  13 import org.w3c.dom.Node;
  14 import org.w3c.dom.NodeList;
  15 /**
  16  * Licensed to the Apache Software Foundation (ASF) under one or more
  17  * contributor license agreements.  See the NOTICE file distributed with
  18  * this work for additional information regarding copyright ownership.
  19  * The ASF licenses this file to You under the Apache License, Version 2.0
  20  * (the "License"); you may not use this file except in compliance with
  21  * the License.  You may obtain a copy of the License at
  22  *
  23  *     http://www.apache.org/licenses/LICENSE-2.0
  24  *
  25  * Unless required by applicable law or agreed to in writing, software
  26  * distributed under the License is distributed on an "AS IS" BASIS,
  27  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  28  * See the License for the specific language governing permissions and
  29  * limitations under the License.
  30  */
  31
  32 /**
  33  *
  34  */
  35 public class BooleanQueryBuilder implements QueryBuilder {
  36
  37         private QueryBuilder factory;
  38
  39         public BooleanQueryBuilder(QueryBuilder factory)
  40         {
  41                 this.factory=factory;
  42         }
  43
  44         /* (non-Javadoc)
  45          * @see org.apache.lucene.xmlparser.QueryObjectBuilder#process(org.w3c.dom.Element)
  46          */
  47         public Query getQuery(Element e) throws ParserException {
  48                 BooleanQuery bq=new BooleanQuery(DOMUtils.getAttribute(e,"disableCoord",false));
  49                 bq.setMinimumNumberShouldMatch(DOMUtils.getAttribute(e,"minimumNumberShouldMatch",0));
  50                 bq.setBoost(DOMUtils.getAttribute(e,"boost",1.0f));
  51
  52                 NodeList nl = e.getChildNodes();
  53                 for(int i=0;i<nl.getLength();i++)
  54                 {
  55                         Node node = nl.item(i);
  56                         if(node.getNodeName().equals("Clause"))
  57                         {
  58                                 Element clauseElem=(Element) node;
  59                                 BooleanClause.Occur occurs=getOccursValue(clauseElem);
  60
  61                                 Element clauseQuery=DOMUtils.getFirstChildOrFail(clauseElem);
  62                                 Query q=factory.getQuery(clauseQuery);
  63                                 bq.add(new BooleanClause(q,occurs));
  64                         }
  65                 }
  66
  67                 return bq;
  68         }
  69         static BooleanClause.Occur getOccursValue(Element clauseElem) throws ParserException
  70         {
  71                 String occs=clauseElem.getAttribute("occurs");
  72                 BooleanClause.Occur occurs=BooleanClause.Occur.SHOULD;
  73                 if("must".equalsIgnoreCase(occs))
  74                 {
  75                         occurs=BooleanClause.Occur.MUST;
  76                 }
  77                 else
  78                 {
  79                         if("mustNot".equalsIgnoreCase(occs))
  80                         {
  81                                 occurs=BooleanClause.Occur.MUST_NOT;
  82                         }
  83                         else
  84                         {
  85                                 if(("should".equalsIgnoreCase(occs))||("".equals(occs)))
  86                                 {
  87                                         occurs=BooleanClause.Occur.SHOULD;
  88                                 }
  89                                 else
  90                                 {
  91                                         if(occs!=null)
  92                                         {
  93                                                 throw new ParserException("Invalid value for \"occurs\" attribute of clause:"+occs);
  94                                         }
  95                                 }
  96                         }
  97                 }
  98                 return occurs;
  99
 100         }
 101
 102 }