SpringBoot / SpringCloud

@EnableDiscoveryClient与@EnableEurekaClient区别

在使用Spring Cloud feign使用中在使用服务发现的时候提到了两种注解，一种为@EnableDiscoveryClient,一种为@EnableEurekaClient,用法上基本一致。

spring cloud中discovery service有许多种实现（eureka、consul、zookeeper等等），@EnableDiscoveryClient基于spring-cloud-commons, @EnableEurekaClient基于spring-cloud-netflix。
其实用更简单的话来说，就是如果选用的注册中心是eureka，那么就推荐@EnableEurekaClient，如果是其他的注册中心，那么推荐使用@EnableDiscoveryClient。

@EnableDiscoveryClient

/** Copyright 2013-2015 the original author or authors.** 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 org.springframework.cloud.client.discovery;import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;import org.springframework.context.annotation.Import;/*** Annotation to enable a DiscoveryClient implementation.* @author Spencer Gibb*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@Import(EnableDiscoveryClientImportSelector.class)
public @interface EnableDiscoveryClient {/*** If true, the ServiceRegistry will automatically register the local server.*/boolean autoRegister() default true;
}

@EnableEurekaClient

/** Copyright 2013-2015 the original author or authors.** 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 org.springframework.cloud.netflix.eureka;import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** Convenience annotation for clients to enable Eureka discovery configuration* (specifically). Use this (optionally) in case you want discovery and know for sure that* it is Eureka you want. All it does is turn on discovery and let the autoconfiguration* find the eureka classes if they are available (i.e. you need Eureka on the classpath as* well).** @author Dave Syer* @author Spencer Gibb*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
public @interface EnableEurekaClient {}

注解@EnableEurekaClient上有@EnableDiscoveryClient注解，
可以说基本就是EnableEurekaClient有@EnableDiscoveryClient的功能，
另外上面的注释中提到，其实@EnableEurekaClient注解就是一种方便使用eureka的注解而已，
可以说使用其他的注册中心后，都可以使用@EnableDiscoveryClient注解，
但是使用@EnableEurekaClient的情景，就是在服务采用eureka作为注册中心的时候，使用场景较为单一