pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / contrib / queryparser / src / java / org / apache / lucene / queryParser / surround / query / DistanceQuery.java

diff --git a/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/DistanceQuery.java b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/DistanceQuery.java
new file mode 100644 (file)
index 0000000..9e40f00
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+++ b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/DistanceQuery.java
@@ -0,0 +1,121 @@
+package org.apache.lucene.queryParser.surround.query;
+/**
+ * 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 java.util.List;
+import java.util.Iterator;
+
+import java.io.IOException;
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.search.Query;
+import org.apache.lucene.search.spans.SpanNearQuery;
+import org.apache.lucene.search.spans.SpanQuery;
+
+public class DistanceQuery extends ComposedQuery implements DistanceSubQuery {
+  public DistanceQuery(
+      List<SrndQuery> queries,
+      boolean infix,
+      int opDistance,
+      String opName,
+      boolean ordered) {
+    super(queries, infix, opName);
+    this.opDistance = opDistance; /* the distance indicated in the operator */
+    this.ordered = ordered;
+  }
+
+  private int opDistance;
+  public int getOpDistance() {return opDistance;}
+  
+  private boolean ordered;
+  public boolean subQueriesOrdered() {return ordered;}
+  
+  public String distanceSubQueryNotAllowed() {
+    Iterator<?> sqi = getSubQueriesIterator();
+    while (sqi.hasNext()) {
+      Object leq = sqi.next();
+      if (leq instanceof DistanceSubQuery) {
+        DistanceSubQuery dsq = (DistanceSubQuery) leq;
+        String m = dsq.distanceSubQueryNotAllowed();
+        if (m != null) {
+          return m; 
+        }
+      } else {
+        return "Operator " + getOperatorName() + " does not allow subquery " + leq.toString();
+      }
+    }
+    return null; /* subqueries acceptable */
+  }
+
+  
+  public void addSpanQueries(SpanNearClauseFactory sncf) throws IOException {
+    Query snq = getSpanNearQuery(sncf.getIndexReader(),
+                                  sncf.getFieldName(),
+                                  getWeight(),
+                                  sncf.getBasicQueryFactory());
+    sncf.addSpanNearQuery(snq);
+  }
+
+  @Override
+  public Query makeLuceneQueryFieldNoBoost(final String fieldName, final BasicQueryFactory qf) {
+    return new Query () {
+      
+      @Override
+      public String toString(String fn) {
+        return getClass().toString() + " " + fieldName + " (" + fn + "?)";
+      }
+      
+      @Override
+      public Query rewrite(IndexReader reader) throws IOException {
+        return getSpanNearQuery(reader, fieldName, getBoost(), qf);
+      }
+      
+    };
+  }
+  
+  public Query getSpanNearQuery(
+          IndexReader reader,
+          String fieldName,
+          float boost,
+          BasicQueryFactory qf) throws IOException {
+    SpanQuery[] spanNearClauses = new SpanQuery[getNrSubQueries()];
+    Iterator<?> sqi = getSubQueriesIterator();
+    int qi = 0;
+    while (sqi.hasNext()) {
+      SpanNearClauseFactory sncf = new SpanNearClauseFactory(reader, fieldName, qf);
+      
+      ((DistanceSubQuery)sqi.next()).addSpanQueries(sncf);
+      if (sncf.size() == 0) { /* distance operator requires all sub queries */
+        while (sqi.hasNext()) { /* produce evt. error messages but ignore results */
+          ((DistanceSubQuery)sqi.next()).addSpanQueries(sncf);
+          sncf.clear();
+        }
+        return SrndQuery.theEmptyLcnQuery;
+      }
+      
+      spanNearClauses[qi] = sncf.makeSpanNearClause();
+
+      qi++;
+    }
+    
+    SpanNearQuery r = new SpanNearQuery(spanNearClauses, getOpDistance() - 1, subQueriesOrdered());
+    r.setBoost(boost);
+    return r;
+  }
+}
+