java - 假装REST客户端: FactoryBean threw exception on object creation

Question

我使用假客户端微服务并收到以下错误 -

$ mvn spring-boot:run 
[INFO] Scanning for projects...
[INFO] 
[INFO] -----------< com.transport.visualizer:transport-visualizer >------------
[INFO] Building transport-visualizer 0.0.1-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] >>> spring-boot-maven-plugin:1.5.7.RELEASE:run (default-cli) > test-compile @ transport-visualizer >>>
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ transport-visualizer ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ transport-visualizer ---
[INFO] Nothing to compile - all classes are up to date
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ transport-visualizer ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory /Users/Chaklader/IdeaProjects/TransportationSimulator/TransportVisualizer/src/test/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ transport-visualizer ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 1 source file to /Users/Chaklader/IdeaProjects/TransportationSimulator/TransportVisualizer/target/test-classes
[WARNING] error reading /Users/Chaklader/.m2/repository/org/springframework/security/spring-security-crypto/4.2.3.RELEASE/spring-security-crypto-4.2.3.RELEASE.jar; zip file is empty
[WARNING] error reading /Users/Chaklader/.m2/repository/org/springframework/security/spring-security-crypto/4.2.3.RELEASE/spring-security-crypto-4.2.3.RELEASE.jar; zip file is empty
[INFO] 
[INFO] <<< spring-boot-maven-plugin:1.5.7.RELEASE:run (default-cli) < test-compile @ transport-visualizer <<<
[INFO] 
[INFO] 
[INFO] --- spring-boot-maven-plugin:1.5.7.RELEASE:run (default-cli) @ transport-visualizer ---
[INFO] Attaching agents: []
21:17:03.282 [main] DEBUG org.springframework.boot.devtools.settings.DevToolsSettings - Included patterns for restart : []
21:17:03.285 [main] DEBUG org.springframework.boot.devtools.settings.DevToolsSettings - Excluded patterns for restart : [/spring-boot-starter/target/classes/, /spring-boot-autoconfigure/target/classes/, /spring-boot-starter-[\w-]+/, /spring-boot/target/classes/, /spring-boot-actuator/target/classes/, /spring-boot-devtools/target/classes/]
21:17:03.286 [main] DEBUG org.springframework.boot.devtools.restart.ChangeableUrls - Matching URLs for reloading : [file:/Users/Chaklader/IdeaProjects/TransportationSimulator/TransportVisualizer/target/classes/]
2020-01-19 21:17:03.760  INFO 12186 --- [  restartedMain] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@578ae32b: startup date [Sun Jan 19 21:17:03 BDT 2020]; root of context hierarchy
2020-01-19 21:17:04.064  INFO 12186 --- [  restartedMain] f.a.AutowiredAnnotationBeanPostProcessor : JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
2020-01-19 21:17:04.117  INFO 12186 --- [  restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'configurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$8452941d] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.5.7.RELEASE)

2020-01-19 21:17:04.520  INFO 12186 --- [  restartedMain] c.c.c.ConfigServicePropertySourceLocator : Fetching config from server at: http://localhost:8888
2020-01-19 21:17:04.622  WARN 12186 --- [  restartedMain] c.c.c.ConfigServicePropertySourceLocator : Could not locate PropertySource: I/O error on GET request for "http://localhost:8888/webapp/default": Connection refused (Connection refused); nested exception is java.net.ConnectException: Connection refused (Connection refused)
2020-01-19 21:17:04.623  INFO 12186 --- [  restartedMain] com.transport.visualizer.Application     : The following profiles are active: production
2020-01-19 21:17:04.649  INFO 12186 --- [  restartedMain] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@7c957d13: startup date [Sun Jan 19 21:17:04 BDT 2020]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@578ae32b
2020-01-19 21:17:05.980  INFO 12186 --- [  restartedMain] o.s.cloud.context.scope.GenericScope     : BeanFactory id=40c925ff-d39d-33d7-9455-85a8db8efdb0
2020-01-19 21:17:06.021  INFO 12186 --- [  restartedMain] f.a.AutowiredAnnotationBeanPostProcessor : JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
2020-01-19 21:17:06.191  INFO 12186 --- [  restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$68389120] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2020-01-19 21:17:06.411  INFO 12186 --- [  restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$8452941d] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2020-01-19 21:17:07.106  INFO 12186 --- [  restartedMain] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2020-01-19 21:17:07.122  INFO 12186 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2020-01-19 21:17:07.124  INFO 12186 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.20
2020-01-19 21:17:07.581  WARN 12186 --- [ost-startStop-1] o.a.tomcat.util.scan.StandardJarScanner  : Failed to scan [file:/Users/Chaklader/.m2/repository/org/springframework/security/spring-security-crypto/4.2.3.RELEASE/spring-security-crypto-4.2.3.RELEASE.jar] from classloader hierarchy

java.util.zip.ZipException: zip file is empty
    at java.util.zip.ZipFile.open(Native Method) ~[na:1.8.0_211]
    at java.util.zip.ZipFile.<init>(ZipFile.java:225) ~[na:1.8.0_211]
    at java.util.zip.ZipFile.<init>(ZipFile.java:155) ~[na:1.8.0_211]
    at java.util.jar.JarFile.<init>(JarFile.java:166) ~[na:1.8.0_211]
    at java.util.jar.JarFile.<init>(JarFile.java:130) ~[na:1.8.0_211]
    at org.apache.tomcat.util.scan.JarFileUrlJar.<init>(JarFileUrlJar.java:60) ~[tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:49) ~[tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:338) ~[tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:288) ~[tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.jasper.servlet.TldScanner.scanJars(TldScanner.java:262) [tomcat-embed-jasper-8.5.20.jar:8.5.20]
    at org.apache.jasper.servlet.TldScanner.scan(TldScanner.java:104) [tomcat-embed-jasper-8.5.20.jar:8.5.20]
    at org.apache.jasper.servlet.JasperInitializer.onStartup(JasperInitializer.java:101) [tomcat-embed-jasper-8.5.20.jar:8.5.20]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5196) [tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) [tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1419) [tomcat-embed-core-8.5.20.jar:8.5.20]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1409) [tomcat-embed-core-8.5.20.jar:8.5.20]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_211]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_211]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_211]
    at java.lang.Thread.run(Thread.java:748) [na:1.8.0_211]

2020-01-19 21:17:07.587  INFO 12186 --- [ost-startStop-1] org.apache.jasper.servlet.TldScanner     : At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
2020-01-19 21:17:07.591  INFO 12186 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2020-01-19 21:17:07.591  INFO 12186 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 2942 ms
2020-01-19 21:17:07.928  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2020-01-19 21:17:07.929  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2020-01-19 21:17:07.929  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2020-01-19 21:17:07.930  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2020-01-19 21:17:07.931  INFO 12186 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2020-01-19 21:17:07.932  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2020-01-19 21:17:07.933  INFO 12186 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'webServlet' to [/h2-console/*]
2020-01-19 21:17:08.576  INFO 12186 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Building JPA container EntityManagerFactory for persistence unit 'default'
2020-01-19 21:17:08.599  INFO 12186 --- [  restartedMain] o.hibernate.jpa.internal.util.LogHelper  : HHH000204: Processing PersistenceUnitInfo [
    name: default
    ...]
2020-01-19 21:17:08.683  INFO 12186 --- [  restartedMain] org.hibernate.Version                    : HHH000412: Hibernate Core {5.0.12.Final}
2020-01-19 21:17:08.685  INFO 12186 --- [  restartedMain] org.hibernate.cfg.Environment            : HHH000206: hibernate.properties not found
2020-01-19 21:17:08.687  INFO 12186 --- [  restartedMain] org.hibernate.cfg.Environment            : HHH000021: Bytecode provider name : javassist
2020-01-19 21:17:08.734  INFO 12186 --- [  restartedMain] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
2020-01-19 21:17:08.868  INFO 12186 --- [  restartedMain] org.hibernate.dialect.Dialect            : HHH000400: Using dialect: org.hibernate.dialect.H2Dialect
2020-01-19 21:17:09.349  INFO 12186 --- [  restartedMain] org.hibernate.tool.hbm2ddl.SchemaUpdate  : HHH000228: Running hbm2ddl schema update
2020-01-19 21:17:09.425  INFO 12186 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
2020-01-19 21:17:09.904  INFO 12186 --- [  restartedMain] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@66bff282: startup date [Sun Jan 19 21:17:09 BDT 2020]; parent: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@7c957d13
2020-01-19 21:17:09.936  INFO 12186 --- [  restartedMain] f.a.AutowiredAnnotationBeanPostProcessor : JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
2020-01-19 21:17:10.275  WARN 12186 --- [  restartedMain] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'vehicleController': Unsatisfied dependency expressed through field 'externalService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'positionTrackingExternalService': Unsatisfied dependency expressed through field 'remoteService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.transport.visualizer.services.RemotePositionMicroserviceCalls': FactoryBean threw exception on object creation; nested exception is java.lang.NullPointerException
2020-01-19 21:17:10.276  INFO 12186 --- [  restartedMain] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@66bff282: startup date [Sun Jan 19 21:17:09 BDT 2020]; parent: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@7c957d13
2020-01-19 21:17:10.278  INFO 12186 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Closing JPA EntityManagerFactory for persistence unit 'default'
2020-01-19 21:17:10.285  INFO 12186 --- [  restartedMain] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2020-01-19 21:17:10.308  INFO 12186 --- [  restartedMain] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2020-01-19 21:17:10.314 ERROR 12186 --- [  restartedMain] o.s.boot.SpringApplication               : Application startup failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'vehicleController': Unsatisfied dependency expressed through field 'externalService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'positionTrackingExternalService': Unsatisfied dependency expressed through field 'remoteService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.transport.visualizer.services.RemotePositionMicroserviceCalls': FactoryBean threw exception on object creation; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) [spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) [spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) [spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) [spring-boot-1.5.7.RELEASE.jar:1.5.7.RELEASE]
    at com.transport.visualizer.Application.main(Application.java:20) [classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_211]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_211]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_211]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_211]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-1.5.7.RELEASE.jar:1.5.7.RELEASE]
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'positionTrackingExternalService': Unsatisfied dependency expressed through field 'remoteService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.transport.visualizer.services.RemotePositionMicroserviceCalls': FactoryBean threw exception on object creation; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.11.RELEASE.jar:4.3.11.RELEASE]



[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  10.394 s
[INFO] Finished at: 2020-01-19T21:17:10+06:00
[INFO] ------------------------------------------------------------------------

我认为错误的部分很重要，

2020-01-19 21:17:07.581  WARN 12186 --- [ost-startStop-1] o.a.tomcat.util.scan.StandardJarScanner  : Failed to scan [file:/Users/Chaklader/.m2/repository/org/springframework/security/spring-security-crypto/4.2.3.RELEASE/spring-security-crypto-4.2.3.RELEASE.jar] from classloader hierarchy

java.util.zip.ZipException: zip file is empty
    at java.util.zip.ZipFile.open(Native Method) ~[na:1.8.0_211]

其次，

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2020-01-19 21:17:10.314 ERROR 12186 --- [  restartedMain] o.s.boot.SpringApplication               : Application startup failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'vehicleController': Unsatisfied dependency expressed through field 'externalService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'positionTrackingExternalService': Unsatisfied dependency expressed through field 'remoteService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.transport.visualizer.services.RemotePositionMicroserviceCalls': FactoryBean threw exception on object creation; nested exception is java.lang.NullPointerException

我的服务等级，

@Service
public class PositionTrackingExternalService {


    @Autowired
    private RemotePositionMicroserviceCalls remoteService;

    @Autowired
    private VehicleRepository repository;

    @HystrixCommand(fallbackMethod = "handleExternalServiceDown")
    public Position getLatestPositionForVehicleFromRemoteMicroservice(String name) {

        Position response = remoteService.getLatestPositionForVehicle(name);

        response.setUpToDate(true);
        return response;
    }

    public Position handleExternalServiceDown(String name) {

        // Read the last known position for this vehicle
        Position position = new Position();
        Vehicle vehicle = repository.findByName(name);

        position.setLat(vehicle.getLat());
        position.setLongitude(vehicle.getLongitude());
        position.setTimestamp(vehicle.getLastRecordedPosition());
        position.setUpToDate(false);

        return position;
    }

}

假客户端界面，

@FeignClient(name = "fleetman-position-tracker")
public interface RemotePositionMicroserviceCalls {

    @GetMapping(value = "/vehicles/{name}")
    public Position getLatestPositionForVehicle(@PathVariable(value = "name") String name);
}

主应用程序，

@SpringBootApplication
@EnableCircuitBreaker
@EnableDiscoveryClient
@EnableFeignClients
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    public RestTemplate restTemplate(RestTemplateBuilder builder) {
        return builder.build();
    }
}

最后，提供了pom.xml文件，

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>com.transport.visualizer</groupId>
    <artifactId>transport-visualizer</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>transport-visualizer</name>
    <description>Vehicle visualizer Application</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.7.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>


    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>

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

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

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

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

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

    </dependencies>

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

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>

        <resources>
            <resource>
                <filtering>true</filtering>
                <directory>src/main/resources</directory>
                <includes>
                    <include>application.properties</include>
                </includes>
            </resource>
        </resources>
    </build>

</project>

这里有什么问题以及如何解决它？

Answer 1

注入(inject) ObjectProvider<RemotePositionMicroserviceCalls> 后似乎可以工作在下面提供的服务类中，

@Service
public class PositionTrackingExternalService {


    @Autowired
    private ObjectProvider<RemotePositionMicroserviceCalls> remoteService;

    @Autowired
    private VehicleRepository repository;

    @HystrixCommand(fallbackMethod = "handleExternalServiceDown")
    public Position getLatestPositionForVehicleFromRemoteMicroservice(String name) {

        Position response = remoteService.getObject().getLatestPositionForVehicle(name);

        response.setUpToDate(true);
        return response;
    }

    public Position handleExternalServiceDown(String name) {

        // Read the last known position for this vehicle
        Position position = new Position();
        Vehicle vehicle = repository.findByName(name);

        position.setLat(vehicle.getLat());
        position.setLongitude(vehicle.getLongitude());
        position.setTimestamp(vehicle.getLastRecordedPosition());
        position.setUpToDate(false);

        return position;
    }

}