使用了最新的Spring Cloud版本Finchley.SR1，在启动Eureka的时候，系统在启动后报错，提示如下：

java.lang.IllegalStateException: Failed to introspect Class [org.springframework.cloud.netflix.hystrix.HystrixCircuitBreakerConfiguration] from ClassLoader [java.net.URLClassLoader@5d0fc2f6]
    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:659) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:556) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:541) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.util.ReflectionUtils.getUniqueDeclaredMethods(ReflectionUtils.java:599) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryMethod(AbstractAutowireCapableBeanFactory.java:724) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:665) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:633) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1489) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:420) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:390) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:511) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:503) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBeansOfType(AbstractApplicationContext.java:1198) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.boot.SpringApplication.getExitCodeFromMappedException(SpringApplication.java:889) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.getExitCodeFromException(SpringApplication.java:875) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.handleExitCode(SpringApplication.java:861) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.handleRunFailure(SpringApplication.java:810) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:338) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at com.powervotex.eureka.Application.main(Application.java:12) [classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_77]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_77]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_77]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_77]
    at org.springframework.boot.maven.AbstractRunMojo$LaunchRunner.run(AbstractRunMojo.java:496) [spring-boot-maven-plugin-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_77]
Caused by: java.lang.NoClassDefFoundError: com/netflix/hystrix/contrib/javanica/aop/aspectj/HystrixCommandAspect
    at java.lang.Class.getDeclaredMethods0(Native Method) ~[na:1.8.0_77]
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701) ~[na:1.8.0_77]
    at java.lang.Class.getDeclaredMethods(Class.java:1975) ~[na:1.8.0_77]
    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:641) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    ... 26 common frames omitted
Caused by: java.lang.ClassNotFoundException: com.netflix.hystrix.contrib.javanica.aop.aspectj.HystrixCommandAspect
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[na:1.8.0_77]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[na:1.8.0_77]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_77]
    ... 30 common frames omitted
 

后来发现新版本的Spring Cloud对Hystrix有要求，Eureka中必须添加对Hystrix的依赖才可以。

在Eureka工程中添加了对Hystrix的依赖后，问题解决。

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>