无知我在设置Spring Boot REST应用程序时遇到了什么问题
在设置我认为是一个简单的Spring Boot Rest api的时候，我一直很困惑我做错了什么。 我确实有建立非常基本的春季应用程序（仍然是学生）的经验，但这是我第一次设置一个Spring Rest应用程序。 我确实在基本文件夹中有应用程序，应用程序似乎启动但是当我转到“localhost：8080 /”时出现404错误。 我假设也许我的pom不正确。 我注意到我的打印跟踪没有显示正在暴露的存储库。 谢谢你的帮助。
主要：
@SpringBootApplication public class App { public static void main(String[] args) { SpringApplication.run(App.class, args); } } BaseEntity：
@MappedSuperclass public abstract class BaseEntity { @Id @GeneratedValue(strategy = GenerationType.AUTO) private final Long id; protected BaseEntity() { id = null; } }
实体：
@Entity public class Course extends BaseEntity{ private String title; private String url; protected Course(){ super(); } public Course(String title, String url) { this(); this.title = title; this.url = url; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getUrl() { return url; } public void setUrl(String url) { this.url = url; } }
知识库
@RepositoryRestResource public interface CourseRepository extends CrudRepository { }
双响炮：
4.0.0 com.teamtreehouse ReviewApi 1.0-SNAPSHOT org.springframework.boot spring-boot-starter-data-jpa 1.5.2.RELEASE org.springframework.boot spring-boot-starter-data-jpa 1.5.2.RELEASE com.h2database h2 1.4.194 org.springframework.boot spring-boot-starter-web 1.5.2.RELEASE org.springframework.data spring-data-rest-core 2.6.3.RELEASE
打印跟踪：
/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/bin/java "-javaagent:/Applications/IntelliJ IDEA CE.app/Contents/lib/idea_rt.jar=50324:/Applications/IntelliJ IDEA CE.app/Contents/bin" -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/lib/tools.jar:/Users/ronaldpitt/Desktop/ReviewApi/target/classes:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-data-jpa/1.5.2.RELEASE/spring-boot-starter-data-jpa-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter/1.5.2.RELEASE/spring-boot-starter-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot/1.5.2.RELEASE/spring-boot-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-autoconfigure/1.5.2.RELEASE/spring-boot-autoconfigure-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-logging/1.5.2.RELEASE/spring-boot-starter-logging-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/ch/qos/logback/logback-classic/1.1.11/logback-classic-1.1.11.jar:/Users/ronaldpitt/.m2/repository/ch/qos/logback/logback-core/1.1.11/logback-core-1.1.11.jar:/Users/ronaldpitt/.m2/repository/org/slf4j/jul-to-slf4j/1.7.24/jul-to-slf4j-1.7.24.jar:/Users/ronaldpitt/.m2/repository/org/slf4j/log4j-over-slf4j/1.7.24/log4j-over-slf4j-1.7.24.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-core/4.3.7.RELEASE/spring-core-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/yaml/snakeyaml/1.17/snakeyaml-1.17.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-aop/1.5.2.RELEASE/spring-boot-starter-aop-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-aop/4.3.7.RELEASE/spring-aop-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/aspectj/aspectjweaver/1.8.9/aspectjweaver-1.8.9.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-jdbc/1.5.2.RELEASE/spring-boot-starter-jdbc-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/apache/tomcat/tomcat-jdbc/8.5.11/tomcat-jdbc-8.5.11.jar:/Users/ronaldpitt/.m2/repository/org/apache/tomcat/tomcat-juli/8.5.11/tomcat-juli-8.5.11.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-jdbc/4.3.7.RELEASE/spring-jdbc-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/hibernate/hibernate-core/5.0.12.Final/hibernate-core-5.0.12.Final.jar:/Users/ronaldpitt/.m2/repository/org/jboss/logging/jboss-logging/3.3.0.Final/jboss-logging-3.3.0.Final.jar:/Users/ronaldpitt/.m2/repository/org/hibernate/javax/persistence/hibernate-jpa-2.1-api/1.0.0.Final/hibernate-jpa-2.1-api-1.0.0.Final.jar:/Users/ronaldpitt/.m2/repository/org/javassist/javassist/3.18.1-GA/javassist-3.18.1-GA.jar:/Users/ronaldpitt/.m2/repository/antlr/antlr/2.7.7/antlr-2.7.7.jar:/Users/ronaldpitt/.m2/repository/org/jboss/jandex/2.0.0.Final/jandex-2.0.0.Final.jar:/Users/ronaldpitt/.m2/repository/dom4j/dom4j/1.6.1/dom4j-1.6.1.jar:/Users/ronaldpitt/.m2/repository/xml-apis/xml-apis/1.0.b2/xml-apis-1.0.b2.jar:/Users/ronaldpitt/.m2/repository/org/hibernate/common/hibernate-commons-annotations/5.0.1.Final/hibernate-commons-annotations-5.0.1.Final.jar:/Users/ronaldpitt/.m2/repository/org/hibernate/hibernate-entitymanager/5.0.12.Final/hibernate-entitymanager-5.0.12.Final.jar:/Users/ronaldpitt/.m2/repository/javax/transaction/javax.transaction-api/1.2/javax.transaction-api-1.2.jar:/Users/ronaldpitt/.m2/repository/org/springframework/data/spring-data-jpa/1.11.1.RELEASE/spring-data-jpa-1.11.1.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-orm/4.3.7.RELEASE/spring-orm-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-context/4.3.7.RELEASE/spring-context-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-beans/4.3.7.RELEASE/spring-beans-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-aspects/4.3.7.RELEASE/spring-aspects-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/com/h2database/h2/1.4.194/h2-1.4.194.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-web/1.5.2.RELEASE/spring-boot-starter-web-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/boot/spring-boot-starter-tomcat/1.5.2.RELEASE/spring-boot-starter-tomcat-1.5.2.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/8.5.11/tomcat-embed-core-8.5.11.jar:/Users/ronaldpitt/.m2/repository/org/apache/tomcat/embed/tomcat-embed-el/8.5.11/tomcat-embed-el-8.5.11.jar:/Users/ronaldpitt/.m2/repository/org/apache/tomcat/embed/tomcat-embed-websocket/8.5.11/tomcat-embed-websocket-8.5.11.jar:/Users/ronaldpitt/.m2/repository/org/hibernate/hibernate-validator/5.3.4.Final/hibernate-validator-5.3.4.Final.jar:/Users/ronaldpitt/.m2/repository/javax/validation/validation-api/1.1.0.Final/validation-api-1.1.0.Final.jar:/Users/ronaldpitt/.m2/repository/com/fasterxml/classmate/1.3.1/classmate-1.3.1.jar:/Users/ronaldpitt/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.8.7/jackson-databind-2.8.7.jar:/Users/ronaldpitt/.m2/repository/com/fasterxml/jackson/core/jackson-core/2.8.7/jackson-core-2.8.7.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-web/4.3.7.RELEASE/spring-web-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-webmvc/4.3.7.RELEASE/spring-webmvc-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-expression/4.3.7.RELEASE/spring-expression-4.3.7.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/data/spring-data-rest-core/2.6.3.RELEASE/spring-data-rest-core-2.6.3.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/spring-tx/4.3.8.RELEASE/spring-tx-4.3.8.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/hateoas/spring-hateoas/0.23.0.RELEASE/spring-hateoas-0.23.0.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/data/spring-data-commons/1.13.3.RELEASE/spring-data-commons-1.13.3.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/springframework/plugin/spring-plugin-core/1.2.0.RELEASE/spring-plugin-core-1.2.0.RELEASE.jar:/Users/ronaldpitt/.m2/repository/org/atteo/evo-inflector/1.2.1/evo-inflector-1.2.1.jar:/Users/ronaldpitt/.m2/repository/com/fasterxml/jackson/core/jackson-annotations/2.8.7/jackson-annotations-2.8.7.jar:/Users/ronaldpitt/.m2/repository/org/slf4j/slf4j-api/1.7.24/slf4j-api-1.7.24.jar:/Users/ronaldpitt/.m2/repository/org/slf4j/jcl-over-slf4j/1.7.24/jcl-over-slf4j-1.7.24.jar:/Users/ronaldpitt/.m2/repository/com/jayway/jsonpath/json-path/2.2.0/json-path-2.2.0.jar:/Users/ronaldpitt/.m2/repository/net/minidev/json-smart/2.2.1/json-smart-2.2.1.jar:/Users/ronaldpitt/.m2/repository/net/minidev/accessors-smart/1.1/accessors-smart-1.1.jar:/Users/ronaldpitt/.m2/repository/org/ow2/asm/asm/5.0.3/asm-5.0.3.jar com.teamtreehouse.App objc[809]: Class JavaLaunchHelper is implemented in both /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/bin/java (0x106e8c4c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x106f544e0). One of the two will be used. Which one is undefined. . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.5.2.RELEASE) 2017-05-08 19:58:30.877 INFO 809 --- [ main] com.teamtreehouse.App : Starting App on Ronalds-MacBook-Pro.local with PID 809 (/Users/ronaldpitt/Desktop/ReviewApi/target/classes started by ronaldpitt in /Users/ronaldpitt/Desktop/ReviewApi) 2017-05-08 19:58:30.880 INFO 809 --- [ main] com.teamtreehouse.App : No active profile set, falling back to default profiles: default 2017-05-08 19:58:30.949 INFO 809 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@38364841: startup date [Mon May 08 19:58:30 EDT 2017]; root of context hierarchy 2017-05-08 19:58:32.540 INFO 809 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$c315e65f] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying) 2017-05-08 19:58:33.015 INFO 809 --- [ main] sbcetTomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http) 2017-05-08 19:58:33.040 INFO 809 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat 2017-05-08 19:58:33.041 INFO 809 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.11 2017-05-08 19:58:33.201 INFO 809 --- [ost-startStop-1] oaccC[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2017-05-08 19:58:33.201 INFO 809 --- [ost-startStop-1] osweb.context.ContextLoader : Root WebApplicationContext: initialization completed in 2256 ms 2017-05-08 19:58:33.404 INFO 809 --- [ost-startStop-1] osbwservlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/] 2017-05-08 19:58:33.410 INFO 809 --- [ost-startStop-1] osbwservlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*] 2017-05-08 19:58:33.411 INFO 809 --- [ost-startStop-1] osbwservlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*] 2017-05-08 19:58:33.411 INFO 809 --- [ost-startStop-1] osbwservlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*] 2017-05-08 19:58:33.411 INFO 809 --- [ost-startStop-1] osbwservlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*] 2017-05-08 19:58:34.119 INFO 809 --- [ main] j.LocalContainerEntityManagerFactoryBean : Building JPA container EntityManagerFactory for persistence unit 'default' 2017-05-08 19:58:34.145 INFO 809 --- [ main] o.hibernate.jpa.internal.util.LogHelper : HHH000204: Processing PersistenceUnitInfo [ name: default ...] 2017-05-08 19:58:34.257 INFO 809 --- [ main] org.hibernate.Version : HHH000412: Hibernate Core {5.0.12.Final} 2017-05-08 19:58:34.260 INFO 809 --- [ main] org.hibernate.cfg.Environment : HHH000206: hibernate.properties not found 2017-05-08 19:58:34.262 INFO 809 --- [ main] org.hibernate.cfg.Environment : HHH000021: Bytecode provider name : javassist 2017-05-08 19:58:34.308 INFO 809 --- [ main] o.hibernate.annotations.common.Version : HCANN000001: Hibernate Commons Annotations {5.0.1.Final} 2017-05-08 19:58:34.558 INFO 809 --- [ main] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.H2Dialect 2017-05-08 19:58:35.091 INFO 809 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000227: Running hbm2ddl schema export 2017-05-08 19:58:35.104 INFO 809 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000230: Schema export complete 2017-05-08 19:58:35.149 INFO 809 --- [ main] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default' 2017-05-08 19:58:36.278 INFO 809 --- [ main] swsmmaRequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@38364841: startup date [Mon May 08 19:58:30 EDT 2017]; root of context hierarchy 2017-05-08 19:58:36.404 INFO 809 --- [ main] swsmmaRequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest) 2017-05-08 19:58:36.406 INFO 809 --- [ main] swsmmaRequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse) 2017-05-08 19:58:36.461 INFO 809 --- [ main] oswshandler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2017-05-08 19:58:36.461 INFO 809 --- [ main] oswshandler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2017-05-08 19:58:36.536 INFO 809 --- [ main] oswshandler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2017-05-08 19:58:36.980 INFO 809 --- [ main] osjeaAnnotationMBeanExporter : Registering beans for JMX exposure on startup 2017-05-08 19:58:37.083 INFO 809 --- [ main] sbcetTomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http) 2017-05-08 19:58:37.091 INFO 809 --- [ main] com.teamtreehouse.App : Started App in 16.892 seconds (JVM running for 17.809) 2017-05-08 20:36:16.889 INFO 809 --- [nio-8080-exec-1] oaccC[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet 'dispatcherServlet' 2017-05-08 20:36:16.889 INFO 809 --- [nio-8080-exec-1] osweb.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started 2017-05-08 20:36:16.918 INFO 809 --- [nio-8080-exec-1] osweb.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 29 ms
您似乎缺少暴露REST服务的任何类。 Spring REST应用程序通常由3层（控制器层，服务层和存储库层）组成，当然，您可以通过网络找到许多其他中间层。
为了举例说明，一个简单的REST应用程序（通常用@Controller注释）的Controllers层公开了REST方法（GET，PUT，POST等），它可以调用服务/存储库层直接从DB获取信息。 但是在现实世界中，这还不够，因此在Service层和Repository层之间添加了一个manager类层。 Manager层包含所有必需的业务逻辑，可以在单个方法中调用多个存储库以实现特定的业务目标。
现在回到您的项目，似乎您有Repository层但不是Controller / Service层。 因此，您没有为客户端提供访问或拨打电话的网关。
@RestController @RequestMapping(path = "/course") public class CourseController{ @Autowired CourseRepository courseRepository; /**implmentations of the course repository needed**/ @RequestMapping(method = RequestMethod.GET) public Course getCourse(){ . // you have to create a courseDto Course course = courseRepository.findById(); // map course pojo to coursedto (if needed/subjective) return course; } }