git add .

spring-cloud/spring-cloud-feign/consumer/src/main/java/com/heibaiying/consumer/feign/CProductFeign.java

@@ -2,13 +2,14 @@ package com.heibaiying.consumer.feign;
 
 import com.heibaiying.common.feign.ProductFeign;
 import com.heibaiying.consumer.config.FeignConfig;
+import com.heibaiying.consumer.feign.impl.CProductFeignImpl;
 import org.springframework.cloud.openfeign.FeignClient;
 
 /**
  * @author : heibaiying
  * @description : 声明式接口调用
  */
-@FeignClient(value = "producer",configuration = FeignConfig.class)
+@FeignClient(value = "producer",configuration = FeignConfig.class,fallback = CProductFeignImpl.class)
 public interface CProductFeign extends ProductFeign {
 
 }

spring-cloud/spring-cloud-feign/consumer/src/main/java/com/heibaiying/consumer/feign/impl/CProductFeignImpl.java

@@ -0,0 +1,31 @@
+package com.heibaiying.consumer.feign.impl;
+
+import com.heibaiying.common.bean.Product;
+import com.heibaiying.consumer.feign.CProductFeign;
+import org.springframework.stereotype.Component;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author : heibaiying
+ * @description : 定义发生错误时候的熔断处理。除了继承自CProductFeign,还需要用@Component声明为spring的组件
+ */
+@Component
+public class CProductFeignImpl implements CProductFeign {
+
+    @Override
+    public List<Product> productList() {
+        return new ArrayList<>();
+    }
+
+    @Override
+    public Product productDetail(int id) {
+        return null;
+    }
+
+    @Override
+    public void save(Product product) {
+
+    }
+}

spring-cloud/spring-cloud-feign/consumer/src/main/resources/application.yml

@@ -9,3 +9,7 @@ eureka:
   client:
     serviceUrl:
       defaultZone: http://localhost:8010/eureka/
+feign:
+  hystrix:
+    # 如果为true，则OpenFign客户端将使用Hystrix断路器进行封装 默认为false
+    enabled: true

spring-cloud/spring-cloud-feign/consumer/src/main/resources/templates/products.ftl

@@ -10,11 +10,15 @@
     <input type="submit" value="新增产品">
 </form>
 <ul>
-    <#list products as product>
-        <li>
-            <a href="/sell/product/${product.id}">${product.name}</a>
-        </li>
-    </#list>
+    <#if (products?size>0) >
+        <#list products as product>
+            <li>
+                <a href="/sell/product/${product.id}">${product.name}</a>
+            </li>
+        </#list>
+    <#else>
+        <h4 style="color: red">当前排队人数过多，请之后再购买！</h4>
+    </#if>
 </ul>
 </body>
 </html>