content: package org.apache.solr.schema;
  
  /**
   * 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.io.IOException;
  import java.util.Locale;
  import java.util.Map;
  import java.util.UUID;
  
  import org.apache.lucene.document.Fieldable;
  import org.apache.lucene.search.SortField;
  import org.apache.solr.common.SolrException;
  import org.apache.solr.response.TextResponseWriter;
  import org.apache.solr.response.XMLWriter;
  
  /**
   * This FieldType accepts UUID string values, as well as the special value 
   * of "NEW" which triggers generation of a new random UUID.
   *
   * @see UUID#toString
   * @see UUID#randomUUID
   * @version $Id: UUIDField.java 945270 2010-05-17 17:45:18Z rmuir $
   */
  public class UUIDField extends FieldType {
    private static final String NEW = "NEW";
    private static final char DASH='-';
  
    @Override
    protected void init(IndexSchema schema, Map<String, String> args) {
      super.init(schema, args);
  
      // Tokenizing makes no sense
      restrictProps(TOKENIZED);
    }
  
    @Override
    public SortField getSortField(SchemaField field, boolean reverse) {
      return getStringSort(field, reverse);
    }
  
    @Override
    public void write(XMLWriter xmlWriter, String name, Fieldable f)
        throws IOException {
      xmlWriter.writeStr(name, f.stringValue());
    }
  
    @Override
    public void write(TextResponseWriter writer, String name, Fieldable f)
        throws IOException {
      writer.writeStr(name, f.stringValue(), false);
    }
  
    /**
     * Generates a UUID if val is either null, empty or "NEW".
     * 
     * Otherwise it behaves much like a StrField but checks that the value given
     * is indeed a valid UUID.
     * 
     * @param val The value of the field
     * @see org.apache.solr.schema.FieldType#toInternal(java.lang.String)
     */
    @Override
    public String toInternal(String val) {
      if (val == null || 0==val.length() || NEW.equals(val)) {
        return UUID.randomUUID().toString().toLowerCase(Locale.ENGLISH);
      } else {
        // we do some basic validation if 'val' looks like an UUID
        if (val.length() != 36 || val.charAt(8) != DASH || val.charAt(13) != DASH
            || val.charAt(18) != DASH || val.charAt(23) != DASH) {
          throw new SolrException(SolrException.ErrorCode.BAD_REQUEST,
              "Invalid UUID String: '" + val + "'");
        }
  
        return val.toLowerCase(Locale.ENGLISH);
      }
    }
  
    public String toInternal(UUID uuid) {
      return uuid.toString().toLowerCase(Locale.ENGLISH);
    }
  
    @Override
    public UUID toObject(Fieldable f) {
      return UUID.fromString(f.stringValue());
    }
  }
  