/*
    * 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.hadoop.hbase.filter;
  
  import com.google.protobuf.InvalidProtocolBufferException;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  import org.apache.hadoop.hbase.exceptions.DeserializationException;
  import org.apache.hadoop.hbase.protobuf.generated.ComparatorProtos;
  import org.apache.hadoop.hbase.util.Bytes;
  
  /**
   * A long comparator which numerical compares against the specified byte array
   */
  @InterfaceAudience.Public
  @InterfaceStability.Stable
  public class LongComparator extends ByteArrayComparable {
      private Long longValue;
  
      public LongComparator(long value) {
        super(Bytes.toBytes(value));
        this.longValue = value;
      }
  
      @Override
      public int compareTo(byte[] value, int offset, int length) {
        Long that = Bytes.toLong(value, offset, length);
        return this.longValue.compareTo(that);
      }
  
      /**
       * @return The comparator serialized using pb
       */
      @Override
      public byte [] toByteArray() {
          ComparatorProtos.LongComparator.Builder builder =
                  ComparatorProtos.LongComparator.newBuilder();
          builder.setComparable(super.convert());
          return builder.build().toByteArray();
      }
  
      /**
       * @param pbBytes A pb serialized {@link LongComparator} instance
       * @return An instance of {@link LongComparator} made from <code>bytes</code>
       * @throws org.apache.hadoop.hbase.exceptions.DeserializationException
       * @see #toByteArray
       */
      public static LongComparator parseFrom(final byte [] pbBytes)
              throws DeserializationException {
          ComparatorProtos.LongComparator proto;
          try {
              proto = ComparatorProtos.LongComparator.parseFrom(pbBytes);
          } catch (InvalidProtocolBufferException e) {
              throw new DeserializationException(e);
          }
          return new LongComparator(Bytes.toLong(proto.getComparable().getValue().toByteArray()));
      }
  
      /**
       * @param other
       * @return true if and only if the fields of the comparator that are serialized
       * are equal to the corresponding fields in other.  Used for testing.
       */
      boolean areSerializedFieldsEqual(LongComparator other) {
          if (other == this) return true;
          return super.areSerializedFieldsEqual(other);
      }
  }