在用struts配置数据源的时候，容易出现以下错误：
信息: Starting Servlet Engine: Apache Tomcat/6.0.13
2008-10-12 9:31:06 org.apache.struts.action.ActionServlet initModuleDataSources
严重: Initializing application data source mysql
java.lang.ClassNotFoundException: org.apache.commons.dbcp.BasicDataSource
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1358)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1204)
at org.apache.struts.util.RequestUtils.applicationClass(RequestUtils.java:117)
at org.apache.struts.util.RequestUtils.applicationInstance(RequestUtils.java:143)
at org.apache.struts.action.ActionServlet.initModuleDataSources(ActionServlet.java:805)
at org.apache.struts.action.ActionServlet.init(ActionServlet.java:335)
at javax.servlet.GenericServlet.init(GenericServlet.java:212)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:981)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4042)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4348)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:920)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:883)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1138)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
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:566)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
2007-12-17 19:31:06 org.apache.catalina.core.ApplicationContext log
信息: Marking servlet action as unavailable
2007-12-17 19:31:06 org.apache.catalina.core.StandardContext loadOnStartup
严重: Servlet /huqianhao threw load() exception
javax.servlet.UnavailableException: Initializing application data source mysql
at org.apache.struts.action.ActionServlet.initModuleDataSources(ActionServlet.java:812)
at org.apache.struts.action.ActionServlet.init(ActionServlet.java:335)
at javax.servlet.GenericServlet.init(GenericServlet.java:212)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:981)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4042)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4348)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:920)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:883)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1138)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
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:566)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
2007-12-17 19:31:06 org.apache.coyote.http11.Http11Protocol start
信息: Starting Coyote HTTP/1.1 on http-8080
2007-12-17 19:31:07 org.apache.jk.common.ChannelSocket init
信息: JK: ajp13 listening on /0.0.0.0:8009
2007-12-17 19:31:07 org.apache.jk.server.JkMain start
信息: Jk running ID=0 time=0/63 config=null
2007-12-17 19:31:07 org.apache.catalina.startup.Catalina start
信息: Server startup in 2848 ms
其实这主要与struts1.2中自动生成的datasource代码和你在lib中加入的jar包（主要是commons-dbcp那个包）不匹配的原因，譬如在commons-dbcp-1.2.2中查看源码可知道它用的属性名是driverClassName,username,defaultReadOnly等，我在struts-config.xml中代码如下
<data-sources >
<data-source key="org.apache.struts.action.DATA_SOURCE" type="org.apache.commons.dbcp.BasicDataSource">
<set-property property="password" value="" />
<set-property property="username" value="root" />
<set-property property="driverClassName" value="com.mysql.jdbc.Driver" />
<set-property property="description" value="datasource to mysql" />
<set-property property="url" value="jdbc:mysql://127.0.0.1:3306/test" />
<set-property property="defaultReadOnly" value="false" />
<set-property property="defaultAutoCommit" value="false" />
</data-source>
</data-sources>
但是struts自动给的生成的代码里面有几个属性名和这里有出入，并且有几个名可能在这里没有定义，所以你可以在加入jar包之后，再根据它的定义修改自己的代码即可