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.demo.dubbo.demo2;
  
  import java.util.Collections;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  
  import com.alibaba.csp.sentinel.adapter.dubbo.DubboAdapterGlobalConfig;
  import com.alibaba.csp.sentinel.concurrent.NamedThreadFactory;
  import com.alibaba.csp.sentinel.demo.dubbo.consumer.ConsumerConfiguration;
  import com.alibaba.csp.sentinel.demo.dubbo.consumer.FooServiceConsumer;
  import com.alibaba.csp.sentinel.slots.block.RuleConstant;
  import com.alibaba.csp.sentinel.slots.block.SentinelRpcException;
  import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
  import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
  import com.alibaba.dubbo.rpc.RpcResult;
  
  import org.springframework.context.annotation.AnnotationConfigApplicationContext;
  
  /**
   * Please add the following VM arguments:
   * <pre>
   * -Djava.net.preferIPv4Stack=true
   * -Dcsp.sentinel.api.port=8721
   * -Dproject.name=dubbo-consumer-demo
   * </pre>
   *
   * @author Eric Zhao
   */
  public class FooConsumerBootstrap {
  
      private static final String RES_KEY = "com.alibaba.csp.sentinel.demo.dubbo.FooService:sayHello(java.lang.String)";
      private static final String INTERFACE_RES_KEY = "com.alibaba.csp.sentinel.demo.dubbo.FooService";
  
      @SuppressWarnings("PMD.ThreadPoolCreationRule")
      private static final ExecutorService pool = Executors.newFixedThreadPool(10,
          new NamedThreadFactory("dubbo-consumer-pool"));
  
      public static void main(String[] args) {
          initFlowRule();
  
          AnnotationConfigApplicationContext consumerContext = new AnnotationConfigApplicationContext();
          consumerContext.register(ConsumerConfiguration.class);
          consumerContext.refresh();
  
          FooServiceConsumer service = consumerContext.getBean(FooServiceConsumer.class);
          for (int i = 0; i < 10; i++) {
              pool.submit(() -> {
                  try {
                      String message = service.sayHello("Eric");
                      System.out.println("Success: " + message);
                  } catch (SentinelRpcException ex) {
                      System.out.println("Blocked");
                  } catch (Exception ex) {
                      ex.printStackTrace();
                  }
              });
              pool.submit(() -> System.out.println("Another: " + service.doAnother()));
          }
      }
  
      private static void initFlowRule() {
          FlowRule flowRule = new FlowRule();
          flowRule.setResource(RES_KEY);
          flowRule.setCount(5);
          flowRule.setGrade(RuleConstant.FLOW_GRADE_THREAD);
          flowRule.setLimitApp("default");
          FlowRuleManager.loadRules(Collections.singletonList(flowRule));
      }
  
      private static void registerFallback() {
          // Register fallback handler for consumer.
          // If you only want to handle degrading, you need to
          // check the type of BlockException.
          DubboAdapterGlobalConfig.setConsumerFallback((a, b, ex) ->
              new RpcResult("Error: " + ex.getClass().getTypeName()));
      }
  }
  