content: /*
   * 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.
   */
  package org.apache.cassandra.db.marshal;
  
  import java.nio.ByteBuffer;
  import java.util.UUID;
  
  import org.apache.cassandra.cql3.terms.Constants;
  import org.apache.cassandra.cql3.terms.Term;
  import org.apache.cassandra.cql3.functions.ArgumentDeserializer;
  import org.apache.cassandra.serializers.TypeSerializer;
  import org.apache.cassandra.serializers.MarshalException;
  import org.apache.cassandra.serializers.UUIDSerializer;
  import org.apache.cassandra.utils.ByteBufferUtil;
  import org.apache.cassandra.utils.bytecomparable.ByteComparable;
  import org.apache.cassandra.utils.bytecomparable.ByteSource;
  import org.apache.cassandra.utils.bytecomparable.ByteSourceInverse;
  
  public class LexicalUUIDType extends AbstractType<UUID>
  {
      public static class Serializer extends UUIDSerializer {}
      private static final Serializer SERIALIZER = new Serializer();
  
      public static final LexicalUUIDType instance = new LexicalUUIDType();
  
      private static final ArgumentDeserializer ARGUMENT_DESERIALIZER = new DefaultArgumentDeserializer(instance);
  
      private static final ByteBuffer MASKED_VALUE = instance.decompose(UUID.fromString("00000000-0000-0000-0000-000000000000"));
  
      LexicalUUIDType()
      {
          super(ComparisonType.CUSTOM);
      } // singleton
  
      @Override
      public boolean allowsEmpty()
      {
          return true;
      }
  
      @Override
      public boolean isEmptyValueMeaningless()
      {
          return true;
      }
  
      public <VL, VR> int compareCustom(VL left, ValueAccessor<VL> accessorL, VR right, ValueAccessor<VR> accessorR)
      {
          if (accessorL.isEmpty(left) || accessorR.isEmpty(right))
              return Boolean.compare(accessorR.isEmpty(right), accessorL.isEmpty(left));
          return accessorL.toUUID(left).compareTo(accessorR.toUUID(right));
      }
  
      @Override
      public <V> ByteSource asComparableBytes(ValueAccessor<V> accessor, V data, ByteComparable.Version version)
      {
          if (data == null || accessor.isEmpty(data))
              return null;
  
          // fixed-length (hence prefix-free) representation, but
          // we have to sign-flip the highest bytes of the two longs
          return new ByteSource()
          {
              int bufpos = 0;
  
              public int next()
              {
                  if (bufpos >= accessor.size(data))
                      return END_OF_STREAM;
                  int v = accessor.getByte(data, bufpos) & 0xFF;
                  if (bufpos == 0 || bufpos == 8)
                      v ^= 0x80;
                  ++bufpos;
                  return v;
              }
          };
      }
  
      @Override
      public <V> V fromComparableBytes(ValueAccessor<V> accessor, ByteSource.Peekable comparableBytes, ByteComparable.Version version)
      {
          // Optional-style encoding of empty values as null sources
          if (comparableBytes == null)
              return accessor.empty();
  
          long hiBits = ByteSourceInverse.getSignedLong(comparableBytes);
          long loBits = ByteSourceInverse.getSignedLong(comparableBytes);
  
          // Lexical UUIDs are stored as just two signed longs. The decoding of these longs flips their sign bit back, so
          // they can directly be used for constructing the original UUID.
          return UUIDType.makeUuidBytes(accessor, hiBits, loBits);
      }
  
      public ByteBuffer fromString(String source) throws MarshalException
      {
          // Return an empty ByteBuffer for an empty string.
          if (source.isEmpty())
              return ByteBufferUtil.EMPTY_BYTE_BUFFER;
  
          try
          {
              return decompose(UUID.fromString(source));
          }
          catch (IllegalArgumentException e)
          {
              throw new MarshalException(String.format("unable to make UUID from '%s'", source), e);
          }
      }
  
      @Override
      public Term fromJSONObject(Object parsed) throws MarshalException
      {
          try
          {
              return new Constants.Value(fromString((String) parsed));
          }
          catch (ClassCastException exc)
          {
              throw new MarshalException(String.format(
                      "Expected a string representation of a uuid, but got a %s: %s", parsed.getClass().getSimpleName(), parsed));
          }
      }
  
      @Override
      public TypeSerializer<UUID> getSerializer()
      {
          return SERIALIZER;
      }
  
      @Override
      public ArgumentDeserializer getArgumentDeserializer()
      {
          return ARGUMENT_DESERIALIZER;
      }
  
      @Override
      public int valueLengthIfFixed()
      {
          return 16;
      }
  
      @Override
      public ByteBuffer getMaskedValue()
      {
          return MASKED_VALUE;
      }
  }
  