Spring Boot and Vaadin - ClassNotFoundException: org.springframework.web.context.support.WebApplicationObjectSupport - spring-boot

Question

I have generated Spring Boot Vaadin project at start.spring.io with just the Vaadin dependency (Maven project, Spring Boot 1.5.1, Vaadin dependency).
I have unzipped the dowloaded .zip file and imported the project to STS (File -> Import -> Existing Maven Projects). I tried to run the application but I got this exception:
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
The project can be build by Maven (clean install) when skipping tests. With tests enabled it fails with the same error.
I have already tried:
to import project and run it in different IDEs (STS, Eclipse, Idea)
run the application as Spring Boot App, Java Application, from test class
other versions of Spring Boot (1.5.1, 1.4.4)
different Java 8 (jdk1.8.0_65, jdk1.8.0_121)
restart IDE

Answer 1

Based on the comment from p.streef I found the solution. I cleared Maven repository (more precisely I deleted content of .m2\repository\org\springframework folder where Spring .jar files are located) and run the application again. Then it worked.
Edit
It seems like frequent problem. Recently I tried to create a new Spring Boot project with Vaadin, JPA and H2 dependencies. At first I got:
spring boot Error creating bean with name 'entityManagerFactory'
I deleted jars in .m2\repository\org\hibernate and run mvn clean install and got:
spring boot NoClassDefFoundError: javassist/bytecode/ClassFile
I deleted jars in .m2\repository\org\javassist and run mvn clean install
Now it worked. So when you get some error running newly created Spring Boot project saying that some class is missing, clean jars in your Maven repository and try it again.