我一直在完成以下教程：
http://spring.io/guides/gs/rest-service/
我最初能够使代码正常工作（运行完成的教程，发送HTTP消息并获得正确的响应）并成功扩展它。
进一步扩展之后，我遇到了以下异常：
java.lang.IllegalStateException: Could not evaluate condition on org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration#propertySourcesPlaceholderConfigurer due to internal class not found. This can happen if you are @ComponentScanning a springframework package (e.g. if you put a @ComponentScan in the default package by mistake)
at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:51)
at org.springframework.context.annotation.ConditionEvaluator.shouldSkip(ConditionEvaluator.java:92)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForBeanMethod(ConfigurationClassBeanDefinitionReader.java:174)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:136)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:116)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:330)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:243)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:254)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:94)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:611)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:321)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:961)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:950)
at com.aharrison.hello.Application.main(Application.java:15)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)
我已经将代码剥离回到示例中显示的内容，但我仍然遇到异常。
我认为它可能与以下问题有关，虽然它被标记为已关闭：
https://github.com/spring-projects/spring-boot/issues/2050
我对Spring不太熟悉，所以我无法完全理解正在讨论的内容。
以下是我目前的课程：
Greeting.java：
package com.aharrison.hello;
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;
}
}
GreetingController：
package com.aharrison.hello;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import java.util.concurrent.atomic.AtomicLong;
@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));
}
}
Application.java：
package com.aharrison.hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
/**
* Created by Adam on 12/26/2014.
*/
@ComponentScan
@EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
的pom.xml：
<?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.aharrison</groupId>
<artifactId>SpringRestAPI</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>1.2.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>1.6.1.RELEASE</version>
</dependency>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>2.12.2</version>
</dependency>
</dependencies>
问题：
提前致谢。
答案 0 :(得分：3)
当我运行你提供的代码时，一切正常。我必须做的唯一改变是pom.xml我添加了以下内容：
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.2.0.RELEASE</version>
</parent>
这将启用整个 Spring Boot 机制，这是您启动应用程序所必需的。
请参阅下面的测试运行成功输出：
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.2.0.RELEASE)
2014-12-27 17:41:12.472 INFO 4065 --- [ main] com.aharrison.hello.Application : Starting Application on My-MacBook-Pro.local with PID 4065 (/Users/wassgren/test/target/test-classes started by wassgren in /Users/wassgren/test/test-di)
2014-12-27 17:41:12.506 INFO 4065 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@4a668b6e: startup date [Sat Dec 27 17:41:12 CET 2014]; root of context hierarchy
2014-12-27 17:41:13.407 INFO 4065 --- [ main] o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition for bean 'beanNameViewResolver': 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]]
2014-12-27 17:41:14.186 INFO 4065 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration' of type [class org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2014-12-27 17:41:14.703 INFO 4065 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080/http
2014-12-27 17:41:15.047 INFO 4065 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2014-12-27 17:41:15.048 INFO 4065 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.0.15
2014-12-27 17:41:15.154 INFO 4065 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2014-12-27 17:41:15.154 INFO 4065 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2651 ms
2014-12-27 17:41:16.399 INFO 4065 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2014-12-27 17:41:16.404 INFO 4065 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2014-12-27 17:41:16.404 INFO 4065 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2014-12-27 17:41:16.907 INFO 4065 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@4a668b6e: startup date [Sat Dec 27 17:41:12 CET 2014]; root of context hierarchy
2014-12-27 17:41:16.979 INFO 4065 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/greeting],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public com.aharrison.hello.Greeting com.aharrison.hello.GreetingController.greeting(java.lang.String)
2014-12-27 17:41:16.981 INFO 4065 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" 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)
2014-12-27 17:41:16.981 INFO 4065 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],methods=[],params=[],headers=[],consumes=[],produces=[text/html],custom=[]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest)
2014-12-27 17:41:17.013 INFO 4065 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2014-12-27 17:41:17.014 INFO 4065 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2014-12-27 17:41:17.059 INFO 4065 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2014-12-27 17:41:17.206 INFO 4065 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2014-12-27 17:41:17.292 INFO 4065 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080/http
2014-12-27 17:41:17.294 INFO 4065 --- [ main] com.aharrison.hello.Application : Started Application in 5.245 seconds (JVM running for 6.088)
答案 1 :(得分：1)
删除位于Application类上方的@ComponentScan。如果您需要扫描的类与Application类在同一个包中，@ SpringBootApplication默认添加它。
答案 2 :(得分：0)
Spring Boot 1.2.2发布，我建议升级到新版本，因为它附带了大量的修复程序。它还使用了spring-security 3.2.6。当您声明任何或覆盖默认情况下的依赖关系时，您必须非常小心，因为启动已经包含了大部分依赖关系。使用带有弹簧安全装置3.2.5的弹簧靴1.2.2时遇到了同样的问题但是当我回到弹簧靴1.2.1时，一切都很好。
答案 3 :(得分：0)
在应用程序类上放置@SpringBootApplication批注，并将该应用程序类放置在相同的包或被调用类的父包中将解决此问题。