ClassNotFoundException在服务器启动期间在Tomcat,Spring和Eclipse上使用wicket。
在Eclipse中,当我尝试加载服务器时,我遇到了导致404页面的一些错误。
这是stackTrace:
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'plop0' defined in ServletContext resource [/WEB-INF/spring-config/dependenciesInjectionContext.xml]: Cannot resolve reference to bean 'plop1' while setting bean property 'plop1'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'plop1': Injection of persistence fields failed; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.plop2.plop3.presentation.WicketApplication] for bean with name 'wicketApplication' defined in ServletContext resource [/WEB-INF/spring-config/wicketContext.xml]; nested exception is java.lang.ClassNotFoundException: com.plop2.plop3.presentation.WicketApplication
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:275)
...
at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'plop1': Injection of persistence fields failed; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.plop2.plop3.presentation.WicketApplication] for bean with name 'wicketApplication' defined in ServletContext resource [/WEB-INF/spring-config/wicketContext.xml]; nested exception is java.lang.ClassNotFoundException: com.plop2.plop3.presentation.WicketApplication
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(PersistenceAnnotationBeanPostProcessor.java:311)
...
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:269)
... 26 more
Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.plop2.plop3.presentation.WicketApplication] for bean with name 'wicketApplication' defined in ServletContext resource [/WEB-INF/spring-config/wicketContext.xml]; nested exception is java.lang.ClassNotFoundException: com.plop2.plop3.presentation.WicketApplication
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1141)
...
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(PersistenceAnnotationBeanPostProcessor.java:308)
... 37 more
Caused by: java.lang.ClassNotFoundException: com.plop2.plop3.presentation.WicketApplication
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1676)
...
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1138)
... 49 more
plop3-admin-provider-wicket的pom.xml:
<parent>
<groupId>com.plop2.plop3</groupId>
<artifactId>plop3</artifactId>
<version>1.0.0</version>
<relativePath>../pom.xml</relativePath>
</parent>
<artifactId>plop3-admin-provider-wicket</artifactId>
<packaging>jar</packaging>
<name>${project.artifactId}(${project.packaging})</name>
<dependencies>
...
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
</dependency>
...
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket</artifactId>
</dependency>
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket-extensions</artifactId>
</dependency>
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket-datetime</artifactId>
</dependency>
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket-jmx</artifactId>
</dependency>
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket-spring</artifactId>
</dependency>
</dependencies>
<build>
<resources>
<resource>
<filtering>true</filtering>
<directory>src/main/java</directory>
<includes>
<include>**/*.html</include>
<include>**/*.properties</include>
</includes>
</resource>
</resources>
<testResources>
<testResource>
<filtering>true</filtering>
<directory>src/test/resources</directory>
</testResource>
</testResources>
</build>
plop3-admin-war的pom.xml:
<parent>
<groupId>com.plop2.plop3</groupId>
<artifactId>plop3</artifactId>
<version>1.0.0</version>
<relativePath>../pom.xml</relativePath>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>plop3-admin-war</artifactId>
<packaging>war</packaging>
<name>${project.artifactId}(${project.packaging})</name>
<dependencies>
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>plop3-admin-provider-wicket</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
</dependency>
...
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket</artifactId>
</dependency>
...
</dependencies>
<build>
<resources>
<resource>
<filtering>true</filtering>
<directory>src/main/resources</directory>
</resource>
</resources>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<configuration>
<webResources>
<resource>
<directory>src/main/webapp</directory>
<filtering>true</filtering>
</resource>
</webResources>
</configuration>
</plugin>
</plugins>
</build>
plop3-admin-war的web.xml:
<!-- Spring param -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-config/applicationContext.xml</param-value>
</context-param>
<filter>
<filter-name>Spring character encoding filter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Spring character encoding filter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>gassi.filter</filter-name>
<filter-class>com.plop2.plop3.gassi.GassiFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>gassi.filter</filter-name>
<url-pattern>/app/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>wicket.filter</filter-name>
<filter-class>org.apache.wicket.protocol.http.WicketFilter</filter-class>
<init-param>
<param-name>applicationFactoryClassName</param-name>
<param-value>org.apache.wicket.spring.SpringWebApplicationFactory</param-value>
</init-param>
<init-param>
<param-name>configuration</param-name>
<param-value>${configuration.type}</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>wicket.filter</filter-name>
<url-pattern>/app/*</url-pattern>
</filter-mapping>
<listener>
<display-name>spring context loader</display-name>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Listener applicatif -->
<listener>
<display-name>plop3Listener context loader</display-name>
<listener-class>com.plop2.plop3.plop3Listener</listener-class>
</listener>
/plop3-admin-war/src/main/webapp/WEB-INF/spring-config/applicationContext.xml:
<import resource="applicationPropertiesContext.xml" />
<import resource="dependenciesInjectionContext.xml" />
<import resource="jpaDaoContext.xml" />
<import resource="transactionContext.xml" />
<import resource="wicketContext.xml" />
然后是/plop3-admin-war/src/main/webapp/WEB-INF/spring-config/wicketContext.xml:
<bean id="wicketApplication" name="wicketApplication"
class="com.plop2.plop3.presentation.WicketApplication" scope="singleton">
</bean>
我不明白为什么无法加载类,plop3-admin-provider-wicket出现在plop3-admin-war Maven依赖列表中。
这让我疯狂,两天我就在它身上。
答案 0 :(得分:1)
尝试构建WAR并将其部署到完全在eclipse之外运行的tomcat,方法是将WAR放在webapps目录中并运行启动脚本。
这将确定问题是库依赖项还是eclipse工作区设置。
如果您怀疑工作区设置,请尝试关闭eclipse中的所有项目并从工作区中删除它们。从命令行执行mvn clean install
并确保其有效。
然后删除以下所有eclipse文件:.project
,.classpath
和.settings
,选择Import as Maven Project
并再试一次,确保eclipse使用相同的maven并且相同settings.xml作为命令行。
如果问题仍然存在,请尝试在web.xml的最开头添加ServletContextListener
,并打印出所涉及的某些类的位置:
System.out.println("All locations of missing class WicketApplication: " + getClass().getclassLoader().getResources("com/plop2/plop3/presentation/WicketApplication.class") );
System.out.println("Currently used version of WicketApplication: " + getClass().getclassLoader().getResource("com/plop2/plop3/presentation/WicketApplication.class") );
对于未找到类的异常有两种解释:要么类不在类路径上(因为jar不在那里或由于eclipse类路径问题),要么类在那里但是类不可见需要它,因为需要它的类在服务器类加载器中。
同时检查JHades,我写的一个工具是为了帮助diagnose classpath problems。