content: package org.apache.lucene.analysis.sinks;
  
  /**
   * 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.DateFormat;
  import java.text.ParseException;
  import java.util.Date;
  
  import org.apache.lucene.analysis.TeeSinkTokenFilter.SinkFilter;
  import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
  import org.apache.lucene.util.AttributeSource;
  
  /**
   * Attempts to parse the {@link org.apache.lucene.analysis.Token#termBuffer()} as a Date using a {@link java.text.DateFormat}.
   * If the value is a Date, it will add it to the sink.
   * <p/> 
   *
   **/
  public class DateRecognizerSinkFilter extends SinkFilter {
    public static final String DATE_TYPE = "date";
  
    protected DateFormat dateFormat;
    protected CharTermAttribute termAtt;
    
    /**
     * Uses {@link java.text.SimpleDateFormat#getDateInstance()} as the {@link java.text.DateFormat} object.
     */
    public DateRecognizerSinkFilter() {
      this(DateFormat.getDateInstance());
    }
    
    public DateRecognizerSinkFilter(DateFormat dateFormat) {
      this.dateFormat = dateFormat; 
    }
  
    @Override
    public boolean accept(AttributeSource source) {
      if (termAtt == null) {
        termAtt = source.addAttribute(CharTermAttribute.class);
      }
      try {
        Date date = dateFormat.parse(termAtt.toString());//We don't care about the date, just that we can parse it as a date
        if (date != null) {
          return true;
        }
      } catch (ParseException e) {
    
      }
      
      return false;
    }
  
  }
  