content: /*
   * Copyright (C) 2016-2023 ActionTech.
   * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher.
   */
  
  package com.actiontech.dble.services.manager.response;
  
  import com.actiontech.dble.config.Fields;
  import com.actiontech.dble.net.mysql.*;
  import com.actiontech.dble.services.manager.ManagerService;
  import com.actiontech.dble.util.LongUtil;
  
  import java.nio.ByteBuffer;
  
  import static com.actiontech.dble.backend.mysql.PacketUtil.getField;
  import static com.actiontech.dble.backend.mysql.PacketUtil.getHeader;
  
  public final class ShowSingleValue {
      private ShowSingleValue() {
      }
  
      private static final int FIELD_COUNT = 1;
      private static final ResultSetHeaderPacket HEADER = getHeader(FIELD_COUNT);
      private static final FieldPacket[] FIELDS = new FieldPacket[FIELD_COUNT];
      private static final EOFPacket EOF = new EOFPacket();
  
  
      public static void execute(ManagerService service, String key, long value) {
          int i = 0;
          byte packetId = 0;
          HEADER.setPacketId(++packetId);
  
          FIELDS[i] = getField(key, Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[i].setPacketId(++packetId);
  
          EOF.setPacketId(++packetId);
          ByteBuffer buffer = service.allocate();
  
          // write header
          buffer = HEADER.write(buffer, service, true);
  
          // write fields
          for (FieldPacket field : FIELDS) {
              buffer = field.write(buffer, service, true);
          }
  
          // write eof
          buffer = EOF.write(buffer, service, true);
  
          // write rows
          RowDataPacket row = new RowDataPacket(FIELD_COUNT);
          row.add(LongUtil.toBytes(value));
          row.setPacketId(++packetId);
          buffer = row.write(buffer, service, true);
  
          // write last eof
          EOFRowPacket lastEof = new EOFRowPacket();
          lastEof.setPacketId(++packetId);
  
  
          lastEof.write(buffer, service);
      }
  
  }
  