我已经很多年没有使用Java了，但是现在我想使用Java / Groovy进行Web开发。如今，Spring Boot似乎是最推荐用作框架的选项，因此，我尝试遵循在pluralsight.com上的创建您的第一个Spring Boot应用程序课程来运行我的第一个Hello World。
我过去曾将Groovy用于控制台应用程序。我使用过Eclipse，但是我对Maven或Gradle没有任何经验。现在，我安装了Spring Tool Suite 3。
我无法运行第一个示例应用程序，相反，该程序以错误消息终止（请参见下文）。我应该在浏览器中打开http://localhost:8080，但是找不到服务器。以下是我的文件。
您能帮我发现问题吗？我在Mac上，该项目在STS中设置为Maven项目。
App.java
package com.boot;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* Hello world!
*
*/
@SpringBootApplication
public class App
{
public static void main( String[] args )
{
// System.out.println("test") does work
SpringApplication.run(App.class, args);
}
}
pom.xml
<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.boot</groupId>
<artifactId>das-boot</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.1.RELEASE</version>
</parent>
<name>das-boot</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
输出
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.3.1.RELEASE)
2019-01-03 22:32:08.034 INFO 77010 --- [ main] com.boot.App : Starting App on mb12.local with PID 77010 (/Users/pida/sts-workspace/das-boot/target/classes started by pida in /Users/pida/sts-workspace/das-boot)
2019-01-03 22:32:08.040 INFO 77010 --- [ main] com.boot.App : No active profile set, falling back to default profiles: default
2019-01-03 22:32:08.160 INFO 77010 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@5032714f: startup date [Thu Jan 03 22:32:08 CET 2019]; root of context hierarchy
2019-01-03 22:32:09.263 INFO 77010 --- [ 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]]
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.springframework.cglib.core.ReflectUtils$1 (file:/Users/pida/.m2/repository/org/springframework/spring-core/4.2.4.RELEASE/spring-core-4.2.4.RELEASE.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of org.springframework.cglib.core.ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
2019-01-03 22:32:09.799 WARN 77010 --- [ main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'tomcatEmbeddedServletContainerFactory' defined in class path resource [org/springframework/boot/autoconfigure/web/EmbeddedServletContainerAutoConfiguration$EmbeddedTomcat.class]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.springframework.boot.autoconfigure.web.ServerProperties org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration.properties; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'serverProperties' defined in class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class]: Initialization of bean failed; nested exception is javax.validation.ValidationException: Unable to instantiate Configuration.
2019-01-03 22:32:09.818 ERROR 77010 --- [ main] o.s.boot.SpringApplication : Application startup failed
org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'tomcatEmbeddedServletContainerFactory' defined in class path resource [org/springframework/boot/autoconfigure/web/EmbeddedServletContainerAutoConfiguration$EmbeddedTomcat.class]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.springframework.boot.autoconfigure.web.ServerProperties org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration.properties; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'serverProperties' defined in class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class]: Initialization of bean failed; nested exception is javax.validation.ValidationException: Unable to instantiate Configuration.
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:133) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:532) ~[spring-context-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:764) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.SpringApplication.doRun(SpringApplication.java:357) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:305) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1124) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1113) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at com.boot.App.main(App.java:15) ~[classes/:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'tomcatEmbeddedServletContainerFactory' defined in class path resource [org/springframework/boot/autoconfigure/web/EmbeddedServletContainerAutoConfiguration$EmbeddedTomcat.class]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.springframework.boot.autoconfigure.web.ServerProperties org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration.properties; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'serverProperties' defined in class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class]: Initialization of bean failed; nested exception is javax.validation.ValidationException: Unable to instantiate Configuration.
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.getEmbeddedServletContainerFactory(EmbeddedWebApplicationContext.java:195) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.createEmbeddedServletContainer(EmbeddedWebApplicationContext.java:158) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:130) ~[spring-boot-1.3.1.RELEASE.jar:1.3.1.RELEASE]
// Much output omitted
2019-01-03 22:32:09.823 INFO 77010 --- [ main] .b.l.ClasspathLoggingApplicationListener : Application failed to start with classpath: unknown
答案 0 :(得分：1)
1.3不支持Java 11，它似乎很可能在查看反射访问警告。 Java 11仅在Spring Boot 2.1中受支持。
要么使用JDK8，要么升级该应用程序以使用Spring Boot 2.1。
默认情况下，Spring Boot 1.3.0.RELEASE需要Java 7和Spring Framework 4.1.5或更高版本。您可以将Spring Boot与Java 6一起使用，并进行一些其他配置。有关更多详细信息，请参见第79.9节“如何使用Java 6”。为Maven（3.2+）和Gradle（1.12+）提供了明确的构建支持。 [提示]
尽管您可以将Spring Boot与Java 6或7结合使用，但我们通常建议尽可能使用Java 8。
如前所述，我建议对于Spring Boot不使用任何1.x版本。它的寿命在今年8月结束。
答案 1 :(得分：0)
由于您使用的是Spring Boot，因此它带有内置的Tomcat Web服务器。尝试通过在application.properties文件中添加属性来更改端口nber。
server.port = 8090
答案 2 :(得分：0)