content: package org.apache.lucene.document;
  
  import java.util.Set;
  /**
   * Copyright 2004 The Apache Software Foundation
   *
   * Licensed 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.
   */
  
  /**
   * Declare what fields to load normally and what fields to load lazily
   *
   **/
  public class SetBasedFieldSelector implements FieldSelector {
    
    private Set<String> fieldsToLoad;
    private Set<String> lazyFieldsToLoad;
    
    /**
     * Pass in the Set of {@link Field} names to load and the Set of {@link Field} names to load lazily.  If both are null, the
     * Document will not have any {@link Field} on it.  
     * @param fieldsToLoad A Set of {@link String} field names to load.  May be empty, but not null
     * @param lazyFieldsToLoad A Set of {@link String} field names to load lazily.  May be empty, but not null  
     */
    public SetBasedFieldSelector(Set<String> fieldsToLoad, Set<String> lazyFieldsToLoad) {
      this.fieldsToLoad = fieldsToLoad;
      this.lazyFieldsToLoad = lazyFieldsToLoad;
    }
  
    /**
     * Indicate whether to load the field with the given name or not. If the {@link Field#name()} is not in either of the 
     * initializing Sets, then {@link org.apache.lucene.document.FieldSelectorResult#NO_LOAD} is returned.  If a Field name
     * is in both <code>fieldsToLoad</code> and <code>lazyFieldsToLoad</code>, lazy has precedence.
     * 
     * @param fieldName The {@link Field} name to check
     * @return The {@link FieldSelectorResult}
     */
    public FieldSelectorResult accept(String fieldName) {
      FieldSelectorResult result = FieldSelectorResult.NO_LOAD;
      if (fieldsToLoad.contains(fieldName) == true){
        result = FieldSelectorResult.LOAD;
      }
      if (lazyFieldsToLoad.contains(fieldName) == true){
        result = FieldSelectorResult.LAZY_LOAD;
      }                                           
      return result;
    }
  }