org.springframework.beans.factory.CannotLoadBeanClassException：找不到类

Question

I replaced j2ee.jar with servle-api.com from my tomcat 6.0 installation directory: And that yields the error below. I'm presently trying to figure out the cause. What might the problem be.

I have a the bean defined in a configuration file: Sempedia-service.xml as follows

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
    <bean id="sempediaSearchService"
        class="com.service.SempediaSearchManager" />


</beans>

my web.xml specifies the following beans:

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/Sempedia-service.xml,/WEB-INF/Sempedia-persistence.xml</param-value>
</context-param>

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

Stack Trace

SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.service.SempediaSearchManager] for bean with name 'sempediaSearchService' defined in ServletContext resource [/WEB-INF/Sempedia-service.xml]; nested exception is java.lang.ClassNotFoundException: com.service.SempediaSearchManager
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1141)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:524)
    at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1177)
    at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:758)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:422)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
    at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3934)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4429)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
    at org.apache.catalina.core.StandardHost.start(StandardHost.java:722)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
    at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
    at org.apache.catalina.core.StandardService.start(StandardService.java:516)
    at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:583)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
Caused by: java.lang.ClassNotFoundException: com.service.SempediaSearchManager
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
    at org.springframework.util.ClassUtils.forName(ClassUtils.java:211)
    at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:385)
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1138)
    ... 24 more

Answer 1

The problem is that there is no class called com.service.SempediaSearchManager on your webapp's classpath. The most likely root causes are:

• the fully qualified classname is incorrect in /WEB-INF/Sempedia-service.xml ; ie the class name is something else,

• the class is not in your webapp's /WEB-INF/classes directory tree or a JAR file in the /WEB-INF/lib directory.

EDIT : The only other thing that I can think of is that the ClassDefNotFoundException may actually be a result of an earlier class loading / static initialization problem. Check your log files for the first stack trace, and look the nested exceptions, ie the "caused by" chain. [If a class load fails one time and you or Spring call Class.forName() again for some reason, then Java won't actually try to load a second time. Instead you will get a ClassDefNotFoundException stack trace that does not explain the real cause of the original failure.]

If you are still stumped, you should take Eclipse out of the picture. Create the WAR file in the form that you are eventually going to deploy it, then from the command line:

1. manually shutdown Tomcat

2. clean out your Tomcat webapp directory,

3. copy the WAR file into the webapp directory,

4. start Tomcat.

If that doesn't solve the problem directly, look at the deployed webapp directory on Tomcat to verify that the "missing" class is in the right place.

Answer 2

I got the same error and the cause was the directory:

U:.....WEB\\WebRoot\\WEB-INF\\classes\\com\\yourcompany\\cc\\dao

was corrupted(directory or file not readable or damaged).. solved with

• renaming the directory WEB-INF\\classes as WEB-INF\\classes_old
• Eclipse's Project menu--> Clean (to recreate directories)
• redeploy --> restart server.

Answer 3

Check your dependencies.

<?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 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>SchoolApp</groupId>
  <artifactId>SchoolApp</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>

  <properties>
    <hibernate.version>4.2.0.Final</hibernate.version>
    <mysql.connector.version>5.1.21</mysql.connector.version>
    <spring.version>3.2.2.RELEASE</spring.version>
  </properties>

  <dependencies>
    <!-- DB related dependencies -->
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-core</artifactId>
      <version>${hibernate.version}</version>
    </dependency>
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-entitymanager</artifactId>
      <version>${hibernate.version}</version>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>${mysql.connector.version}</version>
    </dependency>
    <dependency>
      <groupId>commons-dbcp</groupId>
      <artifactId>commons-dbcp</artifactId>
      <version>1.4</version>
    </dependency>
    <dependency>
      <groupId>javassist</groupId>
      <artifactId>javassist</artifactId>
      <version>3.12.1.GA</version>
    </dependency>
    <!-- SPRING -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-orm</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- Spring Security  -->
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-core</artifactId>
      <version>3.1.3.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-web</artifactId>
      <version>3.1.3.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-config</artifactId>
      <version>3.1.3.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-taglibs</artifactId>
      <version>3.1.3.RELEASE</version>
    </dependency>
    <!-- CGLIB is required to process @Configuration classes -->
    <dependency>
      <groupId>cglib</groupId>
      <artifactId>cglib</artifactId>
      <version>2.2.2</version>
    </dependency>
    <!-- Servlet API and JSTL -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.0.1</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>jstl</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>
    <!-- Test -->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.7</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>${spring.version}</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test-mvc</artifactId>
      <version>1.0.0.M1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <repositories>
    <repository>
      <id>spring-maven-milestone</id>
      <name>Spring Maven Milestone Repository</name>
      <url>http://maven.springframework.org/milestone</url>
    </repository>
  </repositories>

  <build>
    <finalName>spr-mvc-hib</finalName>
    <plugins>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.3.2</version>
        <configuration>
          <source>1.7</source>
          <target>1.7</target>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

Answer 4

I have faced similar problem

So

I just do

1.update Maven Project

2.install maven.

Answer 5

i recently experienced this issue when i was trying to build and suddenly the laptop battery ran out of charge. I just removed all the servers from eclipse and then restore it. after doing that, i re-built the war file and it worked.

Answer 6

I have the same problem. I checked my /WEB-INF/classes based on Stephen's recommendation:

the class is not in your webapp's /WEB-INF/classes directory tree or a JAR file in the /WEB-INF/lib directory.

I discovered I have an outdated jar file. Replacing it with the latest jar file solved the issue.

Answer 7

Just leaving this here for future visitors:

In my case the /WEB-INF/classes directory was missing. If you are using Eclipse, make sure the .settings/org.eclipse.wst.common.component is correct (Deployment Assembly in the project settings).

In my case it was missing

    <wb-resource deploy-path="/WEB-INF/classes" source-path="/src/main/resources"/>
    <wb-resource deploy-path="/WEB-INF/classes" source-path="/src/test/resources"/>

This file is also a common source of errors as mentioned by Anuj (missing dependencies of other projects).

Otherwise, hopefully the other answers (or the "Problems" tab) will help you.

Answer 8

i dont know whether it is relevant to your issue, i got similar issue which i got solved by

1) In eclipse right click server and clean

if it still didnt work

2) export the project and delete the project create the project with same name and import the project and add the project to server and run.