content: package org.apache.solr.spelling.suggest.fst;
  
  /**
   * 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 org.apache.lucene.search.suggest.Lookup;
  import org.apache.lucene.search.suggest.fst.FSTLookup;
  import org.apache.solr.common.util.NamedList;
  import org.apache.solr.core.SolrCore;
  import org.apache.solr.spelling.suggest.LookupFactory;
  
  /**
   * Factory for {@link FSTLookup}
   */
  public class FSTLookupFactory extends LookupFactory {
  
    /**
     * The number of separate buckets for weights (discretization). The more buckets,
     * the more fine-grained term weights (priorities) can be assigned. The speed of lookup
     * will not decrease for prefixes which have highly-weighted completions (because these
     * are filled-in first), but will decrease significantly for low-weighted terms (but
     * these should be infrequent, so it is all right).
     * 
     * <p>The number of buckets must be within [1, 255] range.
     */
    public static final String WEIGHT_BUCKETS = "weightBuckets";
  
    /**
     * If <code>true</code>, exact suggestions are returned first, even if they are prefixes
     * of other strings in the automaton (possibly with larger weights). 
     */
    public static final String EXACT_MATCH_FIRST = "exactMatchFirst";
  
    @Override
    public Lookup create(NamedList params, SolrCore core) {
      int buckets = params.get(WEIGHT_BUCKETS) != null
      ? Integer.parseInt(params.get(WEIGHT_BUCKETS).toString())
      : 10;
  
      boolean exactMatchFirst = params.get(EXACT_MATCH_FIRST) != null
      ? Boolean.valueOf(params.get(EXACT_MATCH_FIRST).toString())
      : true;
  
      return new FSTLookup(buckets, exactMatchFirst);
    }
  }
  