在Eclipse IDE中执行程序时出错

Question

在Eclipse中执行程序时出错：

og4j:WARN No appenders could be found for logger (org.springframework.web.context.ContextLoader).
log4j:WARN Please initialize the log4j system properly.
May 21, 2014 5:23:24 PM org.apache.catalina.core.StandardContext listenerStart
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping': Initialization of bean failed; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.gagan.crud.dao.BookDaoImpl] for bean with name 'bookDao' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.gagan.crud.dao.BookDaoImpl
Related cause: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.gagan.crud.dao.BookDaoImpl] for bean with name 'bookDao' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.gagan.crud.dao.BookDaoImpl
Related cause: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.gagan.crud.service.BookServiceImpl] for bean with name 'bookService' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.gagan.crud.service.BookServiceImpl
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:532)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:626)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:389)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:294)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939)
    at