Bootstrapper

发表于： 2021年5月20日 2021年5月20日
分类： Spring Boot, Spring Cloud, 微服务
标签： spring cloud alibaba, springboot, springcloud, 集成

在集成Spring Cloud项目，启动时报如下错误：

java.lang.NoClassDefFoundError: org/springframework/boot/Bootstrapper
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:756)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
	at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
	at org.springframework.cloud.bootstrap.encrypt.DecryptEnvironmentPostProcessor.getTextEncryptor(DecryptEnvironmentPostProcessor.java:83)
	at org.springframework.cloud.bootstrap.encrypt.DecryptEnvironmentPostProcessor.postProcessEnvironment(DecryptEnvironmentPostProcessor.java:69)
	at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:203)
	at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:191)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
	at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:80)
	at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:53)
	at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:342)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:307)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1247)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1236)
	at com.secbro2.springcloud.nacos.NacosApplication.main(NacosApplication.java:10)
Caused by: java.lang.ClassNotFoundException: org.springframework.boot.Bootstrapper
	at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
	... 27 common frames omitted

导致上述错误最主要的原因就是“版本不匹配”。那么解决方案就很简单了，排查一下Spring Boot、Spring Cloud和Spring Cloud Alibaba之间的关系。

它们在集成的过程中是需要对应的版本的。这个版本的对照关系是在不断的发生变化的，针对Spring Cloud的可以查看如下链接获得与Spring Boot的版本关系：https://spring.io/projects/spring-cloud。

springcloud报错java.lang.NoClassDefFoundError: org/springframework/boot/Bootstrapper插图 — Spring Boot和Spring Cloud的版本关系

由于现在Spring Cloud Alibaba也纳入了Spring Cloud体系，因此也可以在官网中访问到Spring Cloud Alibaba的说明：https://spring.io/projects/spring-cloud-alibaba/ 。

Spring Boot/Spring Cloud/Spring Cloud Alibaba集成

这里展示一下本人集成这三个框架的pom文件内容：

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.springcloud</groupId>
    <artifactId>spring-cloud-alibaba-nacos</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-cloud-alibaba-nacos</name>
    <description>springcloud alibaba nacos集成</description>
    <properties>
        <java.version>1.8</java.version>
        <spring-boot.version>2.4.2</spring-boot.version>
        <spring-cloud.version>2020.0.0</spring-cloud.version>
        <cloud-alibaba.version>2021.1</cloud-alibaba.version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

示例项目源码地址：https://github.com/secbr/spring-cloud

springcloud报错java.lang.NoClassDefFoundError: org/springframework/boot/Bootstrapper插图1