Java Spring 问题：出现意外错误（类型=未找到，状态=404）
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Issue With Spring: There was an unexpected error (type=Not Found, status=404)
提问by moonboy
I am going through this book on restful web services with spring. I decided to move away from what they were doing and use java configuration files. For some reason, after switching over to the Java configuration, the service would run (in the console window) correctly but when I actually go to the endpoint on localhost i get this:
我正在阅读这本关于 Spring 的 Restful Web 服务的书。我决定放弃他们正在做的事情并使用 java 配置文件。出于某种原因，在切换到 Java 配置后，该服务将正确运行（在控制台窗口中），但是当我实际转到 localhost 上的端点时，我得到了这个：
White label Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Sat Apr 23 20:48:25 PDT 2016 There was an unexpected error (type=Not Found, status=404). No message available
白标错误页面
此应用程序没有明确的 /error 映射，因此您将其视为后备。
Sat Apr 23 20:48:25 PDT 2016 出现意外错误（类型=未找到，状态=404）。没有可用的消息
And this is the response from the GET request:
这是来自 GET 请求的响应：
{
"timestamp": 1461470029110,
"status": 404,
"error": "Not Found",
"message": "No message available",
"path": "/greeting"
}
The next chapter of this story begins with me going to the getting started page on the Spring website http://spring.io/guides/gs/rest-service/I decided to start a small project recreating their basic tutorial. I will post the code I wrote below for you to see. The problem is, I am having the exact same issue. The service runs but I can't hit the endpoints. I am not sure what is going on and I have seen others with similar issues, but the answers have not applied/helped with mine. I am sure it is something obvious that I am doing wrong and any help would be greatly appreciated. One last piece of information, if at all relevant, I am using IntelliJ IDEA 15 CE as my IDE.
这个故事的下一章从我转到 Spring 网站http://spring.io/guides/gs/rest-service/上的入门页面开始。我决定开始一个小项目，重新创建他们的基本教程。我把我写在下面的代码贴出来给大家看看。问题是，我遇到了完全相同的问题。该服务运行，但我无法到达端点。我不确定发生了什么，我也看到其他人有类似的问题，但答案并没有适用/帮助我的。我确信很明显我做错了，任何帮助将不胜感激。最后一条信息，如果相关的话，我使用 IntelliJ IDEA 15 CE 作为我的 IDE。
The endpoint being hit:
被击中的端点：
http://localhost:8080/greeting
http://localhost:8080/greeting
My controller
我的控制器
@RestController
public class GreetingController {
private static final String template = "Hello, %s!";
private final AtomicLong counter = new AtomicLong();
@RequestMapping("/greeting")
public Greeting greeting(@RequestParam(value = "name", defaultValue = "World")String name) {
return new Greeting(counter.incrementAndGet(), String.format(template, name));
}
}
My Resource Representation class
我的资源表示类
public class Greeting {
private final long id;
private final String content;
public Greeting(long id, String content) {
this.id = id;
this.content = content;
}
public long getId() {
return id;
}
public String getContent() {
return content;
}
}
My Main
我的主要
@SpringBootApplication
public class Application
{
public static void main(String[] args)
{
SpringApplication.run(Application.class, args);
}
}
My POM file
我的 POM 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.organization_name.webservices</groupId>
<artifactId>helloworld</artifactId>
<version>1.0-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.3.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<properties>
<java.version>1.8</java.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>spring-releases</id>
<url>https://repo.spring.io/libs-release</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-releases</id>
<url>https://repo.spring.io/libs-release</url>
</pluginRepository>
</pluginRepositories>
Command line to run
要运行的命令行
mvn spring-boot:run
My complete log from the console
我来自控制台的完整日志
. ____ _ __ _ _
/\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.3.3.RELEASE)
2016-04-23 20:47:53.153 INFO 7898 --- [ main] c.t.webservices.application.Application : Starting Application on Macintosh.local with PID 7898 (/Users/<my_user>/Downloads/B04788_Code/HelloWorld/target/classes started by <my_user> in /Users/<my_user>/Downloads/B04788_Code/HelloWorld)
2016-04-23 20:47:53.156 INFO 7898 --- [ main] c.t.webservices.application.Application : No active profile set, falling back to default profiles: default
2016-04-23 20:47:53.242 INFO 7898 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@68ceda24: startup date [Sat Apr 23 20:47:53 PDT 2016]; root of context hierarchy
2016-04-23 20:47:54.084 INFO 7898 --- [ main] o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition for bean 'beanNameViewResolver' with a different definition: replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.class]]
2016-04-23 20:47:54.811 INFO 7898 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2016-04-23 20:47:54.840 INFO 7898 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2016-04-23 20:47:54.841 INFO 7898 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.0.32
2016-04-23 20:47:54.960 INFO 7898 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2016-04-23 20:47:54.960 INFO 7898 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1736 ms
2016-04-23 20:47:55.214 INFO 7898 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2016-04-23 20:47:55.218 INFO 7898 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2016-04-23 20:47:55.219 INFO 7898 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2016-04-23 20:47:55.219 INFO 7898 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2016-04-23 20:47:55.219 INFO 7898 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2016-04-23 20:47:55.545 INFO 7898 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@68ceda24: startup date [Sat Apr 23 20:47:53 PDT 2016]; root of context hierarchy
2016-04-23 20:47:55.605 INFO 7898 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2016-04-23 20:47:55.606 INFO 7898 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : 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)
2016-04-23 20:47:55.628 INFO 7898 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-04-23 20:47:55.628 INFO 7898 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-04-23 20:47:55.657 INFO 7898 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-04-23 20:47:55.776 INFO 7898 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2016-04-23 20:47:55.848 INFO 7898 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2016-04-23 20:47:55.853 INFO 7898 --- [ main] c.t.webservices.application.Application : Started Application in 3.531 seconds (JVM running for 4.702)
2016-04-23 20:48:19.521 INFO 7898 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet 'dispatcherServlet'
2016-04-23 20:48:19.521 INFO 7898 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started
2016-04-23 20:48:19.533 INFO 7898 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 12 ms
Console update after GET request
GET 请求后的控制台更新
2016-04-23 20:48:19.521 INFO 7898 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started
2016-04-23 20:48:19.533 INFO 7898 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 12 ms
Console after stopping
停止后控制台
2016-04-23 20:53:24.494 INFO 7898 --- [ Thread-2] ationConfigEmbeddedWebApplicationContext : Closing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@68ceda24: startup date [Sat Apr 23 20:47:53 PDT 2016]; root of context hierarchy
2016-04-23 20:53:24.495 INFO 7898 --- [ Thread-2] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans on shutdown
Process finished with exit code 130
Thanks again for any help you can offer. I will keep everyone posted with updates!
再次感谢您提供的任何帮助。我会及时通知大家更新！
采纳答案by markwatsonatx
I believe your issue is related to packages. Your application is defined in com.organization_name.webservices.application. I am guessing your other classes are in a different package that is not a child of com.organization_name.webservices.application. Spring will automatically load controllers that are in the same package or sub-packages, for example:
我相信您的问题与软件包有关。您的应用程序在com.organization_name.webservices.application. 我猜你的其他类在一个不同的包中，它不是com.organization_name.webservices.application. Spring 会自动加载在同一个包或子包中的控制器，例如：
com.organization_name.webservices.application
com.organization_name.webservices.application.controllers
But not packages like this:
但不是这样的包：
com.organization_name.webservices.controllers
You can fix this by either moving your controller (or application), or adding ComponentScanto your Application:
您可以通过移动控制器（或应用程序）或添加ComponentScan到您的应用程序来解决此问题：
@SpringBootApplication
@ComponentScan(basePackageClasses=GreetingController.class)
public class Application {
You should be seeing this in your log:
您应该在日志中看到这一点：
Mapped "{[/greeting]}" onto public com.organization_name.webservices.xxx.Greeting com.organization_name.webservices.xxx.GreetingController.greeting(java.lang.String)
回答by SAN
in pom.xml add the following dependency
在 pom.xml 中添加以下依赖项
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-jasper</artifactId>
<scope>provided</scope>
</dependency>
回答by bula
seems like you are missing thymleaf dependency. Put this inside your pom.xml dependencies
似乎您缺少 thymleaf 依赖项。把它放在你的 pom.xml 依赖项中
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
回答by Waseem akram
This application has no explicit mapping for /error, so you are seeing this as a fallback.
此应用程序没有明确的 /error 映射，因此您将其视为后备。
Mon May 04 08:30:07 IST 2020 There was an unexpected error (type=Not Found, status=404). No message available
Mon May 04 08:30:07 IST 2020 出现意外错误（类型=未找到，状态=404）。没有可用的消息
回答by Waseem akram
This application has no explicit mapping for /error, so you are seeing this as a fallback.
此应用程序没有明确的 /error 映射，因此您将其视为后备。
Mon May 04 09:16:36 IST 2020 There was an unexpected error (type=Not Found, status=404). No message available
Mon May 04 09:16:36 IST 2020 出现意外错误（类型=未找到，状态=404）。没有可用的消息
