Spring Boot + Gradle:如何构建可执行jar

Question

我正在尝试在Spring Boot + Gradle项目中构建一个可执行jar,但现在没有任何作用.这是最简单的结构.可能,Gradle配置中缺少某些东西.

摇篮:

buildscript {
    ext {
        springBootVersion = '1.5.8.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'org.springframework.boot'

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.8

repositories {
    mavenCentral()
}

jar {
    manifest {
        attributes 'Main-Class': 'com.example.demo.DemoApplication'
    }
    from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
}

dependencies {
    compile('org.springframework.boot:spring-boot-starter-web')
}

主配置文件:

@RestController
@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @GetMapping(value = "/")
    public String index() {
        return "index";
    }
}

当我运行像java -jar 1.jar这样的jar文件时,我遇到了这个异常:

[main] ERROR org.springframework.boot.SpringApplication - Applicati
on startup failed
org.springframework.beans.factory.BeanDefinitionStoreException: Failed to proces
s import candidates for configuration class [com.example.demo.DemoApplication];
nested exception is java.lang.IllegalArgumentException: No auto configuration cl
asses found in META-INF/spring.factories. If you are using a custom packaging, m
ake sure that file is correct.
        at org.springframework.context.annotation.ConfigurationClassParser.proce
ssDeferredImportSelectors(ConfigurationClassParser.java:556)
        at org.springframework.context.annotation.ConfigurationClassParser.parse
(ConfigurationClassParser.java:185)
        at org.springframework.context.annotation.ConfigurationClassPostProcesso
r.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:308)
        at org.springframework.context.annotation.ConfigurationClassPostProcesso
r.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:228)
        at org.springframework.context.support.PostProcessorRegistrationDelegate
.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.ja
va:272)
        at org.springframework.context.support.PostProcessorRegistrationDelegate
.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:92)
        at org.springframework.context.support.AbstractApplicationContext.invoke
BeanFactoryPostProcessors(AbstractApplicationContext.java:687)
        at org.springframework.context.support.AbstractApplicationContext.refres
h(AbstractApplicationContext.java:525)
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationConte
xt.refresh(EmbeddedWebApplicationContext.java:122)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.
java:693)
        at org.springframework.boot.SpringApplication.refreshContext(SpringAppli
cation.java:360)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java
:303)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java
:1118)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java
:1107)
        at com.example.demo.DemoApplication.main(DemoApplication.java:13)
Caused by: java.lang.IllegalArgumentException: No auto configuration classes fou
nd in META-INF/spring.factories. If you are using a custom packaging, make sure
that file is correct.
        at org.springframework.util.Assert.notEmpty(Assert.java:277)
        at org.springframework.boot.autoconfigure.AutoConfigurationImportSelecto
r.getCandidateConfigurations(AutoConfigurationImportSelector.java:153)
        at org.springframework.boot.autoconfigure.AutoConfigurationImportSelecto
r.selectImports(AutoConfigurationImportSelector.java:95)
        at org.springframework.context.annotation.ConfigurationClassParser.proce
ssDeferredImportSelectors(ConfigurationClassParser.java:547)
        ... 14 common frames omitted

可能有什么问题？

Answer 1

我创建了一个包含您提供的所有资源的项目.从终端运行"gradle build",切换到/ build/libs然后运行"java -jar artifactname"就可以了.

你试过清理和重新编译吗？您使用的是哪个版本的Gradle？

Answer 2

在Boot 2.x中，bootJar和bootWar任务负责打包应用程序。

bootJar任务负责创建可执行jar文件。一旦应用了Java插件，它将自动创建。

如果未生成可执行jar / war文件，请手动运行以下gradle任务。

$./gradlew bootJar

同样，bootWar会生成可执行的war文件，并在应用war插件后立即创建它。

我们可以使用以下命令执行bootWar任务：

$./gradlew bootWar

请注意，对于Spring Boot 2.x，我们需要使用Gradle 4.0或更高版本。

Answer 3

我最近刚刚尝试使用 2.1.4.Release 和 Gradle 构建的 Spring boot 应用程序。

我从 Windows CMD 中的目录运行以下命令。

gradlew clean build

（系统中需要安装JDK8），我能够看到生成的JAR，

<project-directory>/build/libs/<project-name-version.jar>

希望这对较旧的问题有所帮助。

参考：

Answer 4

在春季启动中，您可以通过以下方式直接创建可执行的jar文件：

springBoot { 
    executable = true 
}

请试试

jar{
    baseName = 'myapp' 
    version = 'version'
}

它将从命令行创建名为myapp-version.jar Do ./myapp-version.jar的jar。它将执行

请参阅以下链接以获取更多信息。https://docs.spring.io/spring-boot/docs/current/reference/html/deployment-install.html