Spring 教學 - Cannot find class [org.apache.commons.dbcp.BasicDataSource]

以上一篇的 DBCP 連接池配置，如果發生以下問題

Exception in thread "main" org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.apache.commons.dbcp.BasicDataSource] for bean with name 'dataSource' defined in class path resource [applicationContext.xml]; nested exception is java.lang.ClassNotFoundException: org.apache.commons.dbcp.BasicDataSource
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.context.support.ClassPathXmlApplicationContext.(ClassPathXmlApplicationContext.java:139)
at org.springframework.context.support.ClassPathXmlApplicationContext.(ClassPathXmlApplicationContext.java:83)
at org.database.shopCarDao.main(shopCarDao.java:20)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.dbcp.BasicDataSource
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
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)




明顯的是　org.springframework.beans.factory.CannotLoadBeanClassException

就是 Spring 在加載 bean 時發生錯誤而無法加載

後面也補上一句  Cannot find class [org.apache.commons.dbcp.BasicDataSource]

看來這是出在配置檔的，如下紅色標示處所示

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"destroy-method="close">

    <property name="driverClassName" value="com.mysql.jdbc.Driver"/>

    <property name="url" value="jdbc:mysql://localhost:3306/shopcar"/>

    <property name="username" value="root"/>

    <property name="password" value="1111"/>

</bean>

所以是缺少了某些 library，而如果你有下載 Spring 的話

可以在目錄下的 lib 裡找到ㄧ個目錄 jakarta-commons

在打下有很多 Apache 基金會所發布的開源套件，找到　commons-dbcp.jar

並把它匯入到你目前專案中或是加至 Eclipse 的環境下即可了

關於更多 DBCP 可以到 http://commons.apache.org/dbcp/ 查看唷

如果如上一篇以一個 Java WEB 專案來配置 DBCP 連接池的話

那可能還需要多加入 commons-pool.jar  喔~