Question

我在start.spring.io中生成了Spring Boot Vaadin项目，只有Vaadin依赖项（Maven项目，Spring Boot 1.5.1，Vaadin依赖项）。

我已解压缩已下载的.zip文件并将项目导入STS（文件 - ＆gt;导入 - ＆gt;现有Maven项目）。我试图运行该应用程序，但我得到了这个例外：

Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/web/context/support/WebApplicationObjectSupport
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
at java.lang.Class.getDeclaredMethods(Class.java:1975)
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:613)
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:524)
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:510)
at org.springframework.util.ReflectionUtils.getUniqueDeclaredMethods(ReflectionUtils.java:570)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryMethod(AbstractAutowireCapableBeanFactory.java:697)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:640)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:609)
at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1484)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:425)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:395)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:515)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:508)
at org.springframework.context.support.AbstractApplicationContext.getBeansOfType(AbstractApplicationContext.java:1189)
at org.springframework.boot.SpringApplication.getExitCodeFromMappedException(SpringApplication.java:862)
at org.springframework.boot.SpringApplication.getExitCodeFromException(SpringApplication.java:848)
at org.springframework.boot.SpringApplication.handleExitCode(SpringApplication.java:834)
at org.springframework.boot.SpringApplication.handleRunFailure(SpringApplication.java:788)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:325)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151)
at com.example.MyvaadinApplication.main(MyvaadinApplication.java:10)

Caused by: java.lang.ClassNotFoundException: org.springframework.web.context.support.WebApplicationObjectSupport
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 60 more

跳过测试时，可以通过Maven（干净安装）构建项目。启用测试后，它会失败并出现相同的错误。

我已经尝试过了：

导入项目并在不同的IDE（STS，Eclipse，Idea）中运行它
从测试类
其他版本的Spring Boot（1.5.1,1.4.4）
不同的Java 8（jdk1.8.0_65，jdk1.8.0_121）
重启IDE

Answer 1

根据p.streef的评论，我找到了解决方案。我清除了Maven存储库（更确切地说，我删除了Spring .jar文件所在的.m2 \ repository \ org \ springframework文件夹的内容）并再次运行应用程序。然后它奏效了。

修改

似乎经常出现问题。最近我尝试用Vaadin，JPA和H2依赖项创建一个新的Spring Boot项目。起初我得到了：

spring boot Error creating bean with name 'entityManagerFactory'

我删除了.m2 \ repository \ org \ hibernate中的jar并运行mvn clean install并得到：

spring boot NoClassDefFoundError: javassist/bytecode/ClassFile

我删除了.m2 \ repository \ org \ javassist中的jar并运行mvn clean install

现在它奏效了。所以当你运行新创建的Spring Boot项目时出现一些错误，说缺少某个类，在Maven存储库中清理jar并重新尝试。

Spring Boot和Vaadin - ClassNotFoundException：org.springframework.web.context.support.WebApplicationObjectSupport

1 个答案: