Spring Boot可执行Fat Jar运行失败问题求助

我用IntelliJ IDEA创建了一个全新的Spring Boot项目，引入了JPA和mysql-connector依赖。

build.gradle.kts 文件内容如下：

import org.jetbrains.kotlin.gradle.tasks.KotlinCompile

plugins {
    id("org.springframework.boot") version "3.1.1"
    id("io.spring.dependency-management") version "1.1.0"
    kotlin("jvm") version "1.8.22"
    kotlin("plugin.spring") version "1.8.22"
    kotlin("plugin.jpa") version "1.8.22"
}

group = "com.example"
version = "0.0.1-SNAPSHOT"

java {
    sourceCompatibility = JavaVersion.VERSION_17
}

repositories {
    mavenCentral()
}

dependencies {
    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
    implementation("org.springframework.boot:spring-boot-starter-web")
    implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
    implementation("org.jetbrains.kotlin:kotlin-reflect")
    runtimeOnly("com.mysql:mysql-connector-j")
    testImplementation("org.springframework.boot:spring-boot-starter-test")
}

tasks.withType<KotlinCompile> {
    kotlinOptions {
        freeCompilerArgs += "-Xjsr305=strict"
        jvmTarget = "17"
    }
}

tasks.withType<Test> {
    useJUnitPlatform()
}

tasks.withType<Jar> {
    duplicatesStrategy = DuplicatesStrategy.INCLUDE
    manifest {
        attributes["Main-Class"] = "com.example.test.TestApplicationKt"
    }
    from(configurations.runtimeClasspath.get().map { if (it.isDirectory) it else zipTree(it) })
}

application.properties 文件内容如下：

spring.datasource.url=jdbc:mysql://localhost:3306/bizzle_db
spring.datasource.username=root
spring.datasource.password=1234
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

问题详情 #

我需要生成Fat Jar部署到Linux服务器，执行了以下步骤：

• 用 ./gradlew jar 命令生成Jar文件
• 用 java -jar file.jar 命令运行Jar包

但运行时出现如下错误，而项目在IntelliJ IDEA中可以正常运行：

11:37:51.608 [main] WARN org.springframework.context.annotation.AnnotationConfigApplicationContext -- 上下文初始化期间遇到异常 - 取消刷新尝试: org.springframework.beans.factory.UnsatisfiedDependencyException: 创建名为 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaConfiguration' 的Bean失败: 通过构造器参数0表达的依赖不满足: 创建名为 'dataSource' 的Bean失败，该Bean定义在类路径资源 [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class] 中: 无法实例化 [com.zaxxer.hikari.HikariDataSource]: 工厂方法 'dataSource' 抛出异常，消息: 无法确定合适的驱动类
11:37:51.610 [main] ERROR org.springframework.boot.SpringApplication -- 应用运行失败
org.springframework.beans.factory.UnsatisfiedDependencyException: 创建名为 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaConfiguration' 的Bean失败: 通过构造器参数0表达的依赖不满足: 创建名为 'dataSource' 的Bean失败，该Bean定义在类路径资源 [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class] 中: 无法实例化 [com.zaxxer.hikari.HikariDataSource]: 工厂方法 'dataSource' 抛出异常，消息: 无法确定合适的驱动类
        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800)
        at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:245)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1352)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1189)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:560)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200)
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:417)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1332)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1162)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:560)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200)
        at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1154)
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:931)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:608)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734)
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:436)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:312)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295)
        at com.example.test.TestApplicationKt.main(TestApplication.kt:13)
Caused by: org.springframework.beans.factory.BeanCreationException: 创建名为 'dataSource' 的Bean失败，该Bean定义在类路径资源 [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class] 中: 无法实例化 [com.zaxxer.hikari.HikariDataSource]: 工厂方法 'dataSource' 抛出异常，消息: 无法确定合适的驱动类
        at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:659)
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:647)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1332)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1162)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:560)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200)
        at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:254)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1417)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1337)
        at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:888)
        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
        ... 27 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: 无法实例化 [com.zaxxer.hikari.HikariDataSource]: 工厂方法 'dataSource' 抛出异常，消息: 无法确定合适的驱动类
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:171)
        at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:655)
        ... 41 common frames omitted
Caused by: org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: 无法确定合适的驱动类
        at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.determineDriverClassName(DataSourceProperties.java:186)
        at org.springframework.boot.autoconfigure.jdbc.PropertiesJdbcConnectionDetails.getDriverClassName(PropertiesJdbcConnectionDetails.java:49)
        at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration.createDataSource(DataSourceConfiguration.java:55)
        at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration$Hikari.dataSource(DataSourceConfiguration.java:117)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:568)
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:139)
        ... 42 common frames omitted

核心原因 #

你自定义的Jar任务没有适配Spring Boot的依赖打包逻辑，且使用了错误的打包命令：./gradlew jar生成的是普通Jar，不会自动包含runtimeOnly类型的依赖（比如MySQL驱动）；而IDEA运行时会自动将所有runtime依赖加入类路径，所以本地运行正常，打包后运行找不到驱动类。

正确做法：使用Spring Boot官方的bootJar任务 #

Spring Boot Gradle插件已经内置了生成可执行Fat Jar的bootJar任务，无需自定义Jar任务，步骤如下：

1. 删除build.gradle.kts中自定义的tasks.withType<Jar>代码块
2. 执行打包命令：

   ./gradlew bootJar
   

3. 生成的可执行Jar在build/libs目录下，文件名格式为{项目名}-{版本号}.jar
4. 运行Jar：

   java -jar build/libs/你的Jar文件名.jar
   

为什么这个方法有效 #

bootJar任务会自动处理所有依赖的打包（包括runtimeOnly的MySQL驱动），同时正确配置主类、依赖加载逻辑等，完全满足Spring Boot项目的Fat Jar部署需求。

内容的提问来源于stack exchange，提问作者Ali Asjad