Could you please provide the detailed error message?

当我在集成 Sentinel 和 Feign 时，运行github上的示例代码，代码地址如下：
https://github.com/alibaba/spring-cloud-alibaba/blob/master/spring-cloud-alibaba-examples/sentinel-example/sentinel-feign-example/sentinel-feign-consumer-example/src/main/java/com/alibaba/cloud/examples/controller/TestController.java

遇到了类似于上述的问题，具体问题日志如下：
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'echoController': Unsatisfied dependency expressed through field 'echoService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.jmlee.hello.sentinel.feign.service.EchoService': FactoryBean threw exception on object creation; nested exception is java.lang.AbstractMethodError: com.alibaba.cloud.sentinel.feign.SentinelContractHolder.parseAndValidateMetadata(Ljava/lang/Class;)Ljava/util/List;

所用版本：

Spring Cloud Version：Hoxton.SR3
Spring Cloud Alibaba Version：2.2.0.RELEASE

@fangjian0423 Could you please take a look?

Hoxton.SR1 中，fegin.context接口的定义为parseAndValidatateMetadata
Hoxton.SR3 中，fegin.context接口的定义为parseAndValidateMetadata。就是之前版本中定义的方法名拼写错误，所以在Hoxton.SR1后面的版本更正过来，所以出现Caused by: java.lang.AbstractMethodError: com.alibaba.cloud.sentinel.feign.SentinelContractHolder.parseAndValidateMetadata(Ljava/lang/Class;)Ljava/util/List;错误。

我目前的解决办法是：在工程合适的地方，新建包com.alibaba.cloud.sentinel.feign。重新修改一下SentinelContractHolder即可

`
public class SentinelContractHolder implements Contract {

private final Contract delegate;

/**
 * map key is constructed by ClassFullName + configKey. configKey is constructed by
 * {@link feign.Feign#configKey}
 */
public final static Map<String, MethodMetadata> METADATA_MAP = new HashMap<>();

public SentinelContractHolder(Contract delegate) {
	this.delegate = delegate;
}

@Override
public List<MethodMetadata> parseAndValidateMetadata(Class<?> targetType) {
	List<MethodMetadata> metadatas = delegate.parseAndValidateMetadata(targetType);
	metadatas.forEach(metadata -> METADATA_MAP
			.put(targetType.getName() + metadata.configKey(), metadata));
	return metadatas;
}

}
`

By reproducing it, I found two ways to solve this:

1. Change Spring Cloud Version from Hoxton.SR3 to Hoxton.RELEASE

2. Remain using Hoxton.SR3, and specified the version of spring-cloud-openfeign-dependencies to 2.2.0.RELEASE.

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-openfeign-dependencies</artifactId>
            <version>2.2.0.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Hoxton.SR3</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-dependencies</artifactId>
            <version>2.2.0.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Note that the spring-cloud-openfeign-dependencies should be in front of spring-cloud-dependencies.

The reason is as @pointerv described.

碰到了相同的问题，谢谢

碰到了同样的问题，多谢

Spring Cloud Alibaba 2.2.0.RELEASE based on Hoxton.RELEASE.

Spring Cloud Alibaba 2.2.1.RELEASE based on Hoxton.SR3 and it's going to release soon.

Closing this issue as SCA 2.2.1.RELEASE has been released. Thanks all :)

Caused by: java.lang.AbstractMethodError: com.alibaba.cloud.sentinel.feign.SentinelContractHolder.parseAndValidatateMetadata(Ljava/lang/Class;)Ljava/util/List;
at feign.ReflectiveFeign$ParseHandlersByName.apply(ReflectiveFeign.java:154) ~[feign-core-10.4.0.jar:na]
at feign.ReflectiveFeign.newInstance(ReflectiveFeign.java:52) ~[feign-core-10.4.0.jar:na]
at feign.Feign$Builder.target(Feign.java:251) ~[feign-core-10.4.0.jar:na]
at org.springframework.cloud.openfeign.HystrixTargeter.target(HystrixTargeter.java:38) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.loadBalance(FeignClientFactoryBean.java:243) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getTarget(FeignClientFactoryBean.java:272) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:252) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:171) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 48 common frames omitted

Caused by: java.lang.AbstractMethodError: com.alibaba.cloud.sentinel.feign.SentinelContractHolder.parseAndValidatateMetadata(Ljava/lang/Class;)Ljava/util/List;
at feign.ReflectiveFeign$ParseHandlersByName.apply(ReflectiveFeign.java:154) ~[feign-core-10.4.0.jar:na]
at feign.ReflectiveFeign.newInstance(ReflectiveFeign.java:52) ~[feign-core-10.4.0.jar:na]
at feign.Feign$Builder.target(Feign.java:251) ~[feign-core-10.4.0.jar:na]
at org.springframework.cloud.openfeign.HystrixTargeter.target(HystrixTargeter.java:38) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.loadBalance(FeignClientFactoryBean.java:243) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getTarget(FeignClientFactoryBean.java:272) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:252) ~[spring-cloud-openfeign-core-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:171) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
... 48 common frames omitted

2.2.1.RELEASE Hoxton.SR3 可以适配了。但是要去中央仓库下载Hoxton.SR3 阿里云仓库还没有