content: package org.apache.lucene.search;
  
  /**
   * 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.text.Collator;
  
  /**
   * A Filter that restricts search results to a range of term
   * values in a given field.
   *
   * <p>This filter matches the documents looking for terms that fall into the
   * supplied range according to {@link
   * String#compareTo(String)}, unless a <code>Collator</code> is provided. It is not intended
   * for numerical ranges; use {@link NumericRangeFilter} instead.
   *
   * <p>If you construct a large number of range filters with different ranges but on the 
   * same field, {@link FieldCacheRangeFilter} may have significantly better performance. 
   * @since 2.9
   */
  public class TermRangeFilter extends MultiTermQueryWrapperFilter<TermRangeQuery> {
      
    /**
     * @param fieldName The field this range applies to
     * @param lowerTerm The lower bound on this range
     * @param upperTerm The upper bound on this range
     * @param includeLower Does this range include the lower bound?
     * @param includeUpper Does this range include the upper bound?
     * @throws IllegalArgumentException if both terms are null or if
     *  lowerTerm is null and includeLower is true (similar for upperTerm
     *  and includeUpper)
     */
    public TermRangeFilter(String fieldName, String lowerTerm, String upperTerm,
                       boolean includeLower, boolean includeUpper) {
        super(new TermRangeQuery(fieldName, lowerTerm, upperTerm, includeLower, includeUpper));
    }
  
    /**
     * <strong>WARNING:</strong> Using this constructor and supplying a non-null
     * value in the <code>collator</code> parameter will cause every single 
     * index Term in the Field referenced by lowerTerm and/or upperTerm to be
     * examined.  Depending on the number of index Terms in this Field, the 
     * operation could be very slow.
     *
     * @param lowerTerm The lower bound on this range
     * @param upperTerm The upper bound on this range
     * @param includeLower Does this range include the lower bound?
     * @param includeUpper Does this range include the upper bound?
     * @param collator The collator to use when determining range inclusion; set
     *  to null to use Unicode code point ordering instead of collation.
     * @throws IllegalArgumentException if both terms are null or if
     *  lowerTerm is null and includeLower is true (similar for upperTerm
     *  and includeUpper)
     */
    public TermRangeFilter(String fieldName, String lowerTerm, String upperTerm,
                       boolean includeLower, boolean includeUpper,
                       Collator collator) {
        super(new TermRangeQuery(fieldName, lowerTerm, upperTerm, includeLower, includeUpper, collator));
    }
  
    /**
     * Constructs a filter for field <code>fieldName</code> matching
     * less than or equal to <code>upperTerm</code>.
     */
    public static TermRangeFilter Less(String fieldName, String upperTerm) {
        return new TermRangeFilter(fieldName, null, upperTerm, false, true);
    }
  
    /**
     * Constructs a filter for field <code>fieldName</code> matching
     * greater than or equal to <code>lowerTerm</code>.
     */
    public static TermRangeFilter More(String fieldName, String lowerTerm) {
        return new TermRangeFilter(fieldName, lowerTerm, null, true, false);
    }
  
    /** Returns the field name for this filter */
    public String getField() { return query.getField(); }
    
    /** Returns the lower value of this range filter */
    public String getLowerTerm() { return query.getLowerTerm(); }
  
    /** Returns the upper value of this range filter */
    public String getUpperTerm() { return query.getUpperTerm(); }
    
    /** Returns <code>true</code> if the lower endpoint is inclusive */
    public boolean includesLower() { return query.includesLower(); }
    
    /** Returns <code>true</code> if the upper endpoint is inclusive */
    public boolean includesUpper() { return query.includesUpper(); }
  
    /** Returns the collator used to determine range inclusion, if any. */
    public Collator getCollator() { return query.getCollator(); }
  }
  