content: /*
   * Copyright 1999-2018 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.csp.sentinel.slots.statistic;
  
  import com.alibaba.csp.sentinel.context.Context;
  import com.alibaba.csp.sentinel.node.DefaultNode;
  import com.alibaba.csp.sentinel.slotchain.ProcessorSlotEntryCallback;
  import com.alibaba.csp.sentinel.slotchain.ResourceWrapper;
  import com.alibaba.csp.sentinel.slots.block.BlockException;
  import com.alibaba.csp.sentinel.slots.block.flow.param.ParameterMetric;
  import com.alibaba.csp.sentinel.slots.block.flow.param.ParameterMetricStorage;
  
  /**
   * @author Eric Zhao
   * @since 0.2.0
   */
  public class ParamFlowStatisticEntryCallback implements ProcessorSlotEntryCallback<DefaultNode> {
  
      @Override
      public void onPass(Context context, ResourceWrapper resourceWrapper, DefaultNode node, int count, Object... args) {
          // The "hot spot" parameter metric is present only if parameter flow rules for the resource exist.
          ParameterMetric parameterMetric = ParameterMetricStorage.getParamMetric(resourceWrapper);
  
          if (parameterMetric != null) {
              parameterMetric.addThreadCount(args);
          }
      }
  
      @Override
      public void onBlocked(BlockException ex, Context context, ResourceWrapper resourceWrapper, DefaultNode param,
                            int count, Object... args) {
          // Here we don't add block count here because checking the type of block exception can affect performance.
          // We add the block count when throwing the ParamFlowException instead.
      }
  }
  