Question

我已经开始玩gradle和spring boot并选择了一些很好的简单教程，如下所示。我的设置也列在下面。

虽然教程声明需要Java 1.8，但我已经读过gradle和boot都可以在Java 1.7上使用。

那么，为什么这个简单的教程不应该适用于Java 1.7？显然......

我按如下方式创建我的gradlew：gradle wrapper --gradle-version 3.0然后在我的项目目录中运行我的gradle build命令作为ususal：./gradlew build && java -jar build/libs/gs-spring-boot-0.1.0.jar。

设定：

操作系统：12.04 LTS 32位
java版本＆＃34; 1.7.0_80＆＃34;
教程：
- https://spring.io/guides/gs/spring-boot/#scratch
- https://docs.gradle.org/current/userguide/gradle_wrapper.html

build.gradle（注意：我指定target / sourceCompatibility = 1.7）：

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:1.4.0.RELEASE")
    }
}

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'spring-boot'

jar {
    baseName = 'gs-spring-boot'
    version =  '0.1.0'
}

repositories {
    mavenCentral()
}

sourceCompatibility = 1.7
targetCompatibility = 1.7

dependencies {
    // tag::jetty[]
    compile("org.springframework.boot:spring-boot-starter-web") {
        exclude module: "spring-boot-starter-tomcat"
    }
    compile("org.springframework.boot:spring-boot-starter-jetty")
    // end::jetty[]
    // tag::actuator[]
    compile("org.springframework.boot:spring-boot-starter-actuator")
    // end::actuator[]
    testCompile("junit:junit")
}

输出：

请注意，错误发生在服务器启动时，即： org.springframework.context.ApplicationContextException: Unable to start embedded container

vagrant@precise32:/vagrant/BootTutorial$ ./gradlew build && java -jar build/libs/gs-spring-boot-0.1.0.jar
:compileJava UP-TO-DATE
:processResources UP-TO-DATE
:classes UP-TO-DATE
:findMainClass
:jar
:bootRepackage
:assemble
:compileTestJava UP-TO-DATE
:processTestResources UP-TO-DATE
:testClasses UP-TO-DATE
:test UP-TO-DATE
:check UP-TO-DATE
:build

BUILD SUCCESSFUL

Total time: 4.835 secs

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.4.0.RELEASE)

2016-09-03 18:57:49.456  INFO 2043 --- [           main] hello.Application                        : Starting Application on precise32 with PID 2043 (/vagrant/BootTutorial/build/libs/gs-spring-boot-0.1.0.jar started by vagrant in /vagrant/BootTutorial)
2016-09-03 18:57:49.518  INFO 2043 --- [           main] hello.Application                        : No active profile set, falling back to default profiles: default
2016-09-03 18:57:50.136  INFO 2043 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@65b0e5: startup date [Sat Sep 03 18:57:50 AEST 2016]; root of context hierarchy
2016-09-03 18:57:58.795  WARN 2043 --- [           main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.context.ApplicationContextException: Unable to start EmbeddedWebApplicationContext due to missing EmbeddedServletContainerFactory bean.
2016-09-03 18:57:59.019 ERROR 2043 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.context.ApplicationContextException: Unable to start EmbeddedWebApplicationContext due to missing EmbeddedServletContainerFactory bean.
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:137) ~[spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:535) ~[spring-context-4.3.2.RELEASE.jar!/:4.3.2.RELEASE]
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:369) [spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:313) [spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1185) [spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1174) [spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at hello.Application.main(Application.java:13) [classes!/:na]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.7.0_80]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[na:1.7.0_80]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.7.0_80]
        at java.lang.reflect.Method.invoke(Method.java:606) ~[na:1.7.0_80]
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [gs-spring-boot-0.1.0.jar:na]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [gs-spring-boot-0.1.0.jar:na]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [gs-spring-boot-0.1.0.jar:na]
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:58) [gs-spring-boot-0.1.0.jar:na]
Caused by: org.springframework.context.ApplicationContextException: Unable to start EmbeddedWebApplicationContext due to missing EmbeddedServletContainerFactory bean.
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.getEmbeddedServletContainerFactory(EmbeddedWebApplicationContext.java:189) ~[spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.createEmbeddedServletContainer(EmbeddedWebApplicationContext.java:162) ~[spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:134) ~[spring-boot-1.4.0.RELEASE.jar!/:1.4.0.RELEASE]
        ... 16 common frames omitted

vagrant@precise32:/vagrant/BootTutorial$

Answer 1

使用Spring Boot 1.4，默认的Jetty版本是9.3，这需要JDK8。

如果你想坚持使用JDK7 you can use Jetty 9.2 as explained in the reference documentation。

Answer 2

你真的看过堆栈吗？它清楚地说“正在使用8080端口”。有两种可能性，要么你有某种服务器或服务监听端口8080，要么你在上次运行的后台有一个悬挂线程。

Answer 3

我不确定你的Application.java类是怎么样的。但是我猜你错过了这样的东西。

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class Application {
  public static void main(String[] args) {
    SpringApplication.run(YourClassToRun.class, args);
  }
}

使用gradle 3和java 7的spring boot在服务器启动时失败

3 个答案: