content: /*
   * Copyright 2014-2025 Real Logic Limited.
   *
   * 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
   *
   * https://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 io.aeron.command;
  
  import org.agrona.MutableDirectBuffer;
  
  import static org.agrona.BitUtil.SIZE_OF_INT;
  import static org.agrona.BitUtil.SIZE_OF_LONG;
  
  /**
   * Message to denote that a Counter has become available or unavailable.
   *
   * @see ControlProtocolEvents
   * <pre>
   *   0                   1                   2                   3
   *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   *  |                         Correlation ID                        |
   *  |                                                               |
   *  +---------------------------------------------------------------+
   *  |                           Counter ID                          |
   *  +---------------------------------------------------------------+
   * </pre>
   */
  public class CounterUpdateFlyweight
  {
      /**
       * Length of the header.
       */
      public static final int LENGTH = SIZE_OF_LONG + SIZE_OF_INT;
      private static final int CORRELATION_ID_OFFSET = 0;
      private static final int COUNTER_ID_OFFSET = CORRELATION_ID_OFFSET + SIZE_OF_LONG;
  
      private MutableDirectBuffer buffer;
      private int offset;
  
      /**
       * Wrap the buffer at a given offset for updates.
       *
       * @param buffer to wrap
       * @param offset at which the message begins.
       * @return this for a fluent API.
       */
      public final CounterUpdateFlyweight wrap(final MutableDirectBuffer buffer, final int offset)
      {
          this.buffer = buffer;
          this.offset = offset;
  
          return this;
      }
  
      /**
       * Get the correlation id field.
       *
       * @return correlation id field.
       */
      public long correlationId()
      {
          return buffer.getLong(offset + CORRELATION_ID_OFFSET);
      }
  
      /**
       * Set the correlation id field.
       *
       * @param correlationId field value.
       * @return this for a fluent API.
       */
      public CounterUpdateFlyweight correlationId(final long correlationId)
      {
          buffer.putLong(offset + CORRELATION_ID_OFFSET, correlationId);
  
          return this;
      }
  
      /**
       * The counter id.
       *
       * @return counter id.
       */
      public int counterId()
      {
          return buffer.getInt(offset + COUNTER_ID_OFFSET);
      }
  
      /**
       * Set counter id field.
       *
       * @param counterId field value.
       * @return this for a fluent API.
       */
      public CounterUpdateFlyweight counterId(final int counterId)
      {
          buffer.putInt(offset + COUNTER_ID_OFFSET, counterId);
  
          return this;
      }
  }
  