content: /*
   * Copyright 1999-$toady.year Alibaba Group Holding Ltd.
   *
   * 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
   *
   *      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 com.alibaba.nacos.config.server.service.query.handler;
  
  import com.alibaba.nacos.common.utils.StringUtils;
  import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainRequest;
  import com.alibaba.nacos.config.server.service.query.model.ConfigQueryChainResponse;
  
  import java.io.IOException;
  
  /**
   * SpecialTagNotFound Handler.
   * This class represents special tag not found handler in the configuration query processing chain.
   *
   * @author Nacos
   */
  public class SpecialTagNotFoundHandler extends AbstractConfigQueryHandler {
      
      private static final String SPECIAL_TAG_NOT_FOUND_HANDLER = "specialTagNotFoundHandler";
      
      @Override
      public String getName() {
          return SPECIAL_TAG_NOT_FOUND_HANDLER;
      }
      
      @Override
      public ConfigQueryChainResponse handle(ConfigQueryChainRequest request) throws IOException {
          if (StringUtils.isNotBlank(request.getTag())) {
              ConfigQueryChainResponse response = new ConfigQueryChainResponse();
              response.setStatus(ConfigQueryChainResponse.ConfigQueryStatus.SPECIAL_TAG_CONFIG_NOT_FOUND);
              return response;
          } else {
              return nextHandler.handle(request);
          }
      }
  }