请问您购买的JSP项目开发全程实例是第几版？封面是什么颜色的？出现这个异常信息有两种可能，一种是Jar包没有放置正确，另一种可能是数据库连接失败。
您使用的是Struts 2.0的Jar包吗？
视频中介绍的Jar包是连接SQL Server 2000数据库的，如果您使用的是SQL Server 2005数据库，那么应该是sqljdbc4.jar。

书是第3版的，白色封面。光盘带的是sqljdbc4.jar，都是放在\WebRoot\WEB-INF\lib文件夹内。并且重新编译过也是不行。
都是以下的错误提示。
HTTP Status 500 -

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Filter execution threw an exception
root cause

java.lang.ExceptionInInitializerError
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
java.lang.reflect.Constructor.newInstance(Unknown Source)
java.lang.Class.newInstance(Unknown Source)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:123)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:154)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:143)
com.opensymphony.xwork2.ObjectFactory.buildAction(ObjectFactory.java:113)
com.opensymphony.xwork2.DefaultActionInvocation.createAction(DefaultActionInvocation.java:275)
com.opensymphony.xwork2.DefaultActionInvocation.init(DefaultActionInvocation.java:365)
com.opensymphony.xwork2.DefaultActionInvocation.access$000(DefaultActionInvocation.java:38)
com.opensymphony.xwork2.DefaultActionInvocation$1.doProfiling(DefaultActionInvocation.java:83)
com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455)
com.opensymphony.xwork2.DefaultActionInvocation.<init>(DefaultActionInvocation.java:74)
com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:189)
org.apache.struts2.impl.StrutsActionProxyFactory.createActionProxy(StrutsActionProxyFactory.java:41)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:494)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:419)
root cause

java.lang.NullPointerException
com.yxq.dao.DB.getRs(DB.java:61)
com.yxq.dao.OpDB.OpGetListBox(OpDB.java:23)
com.yxq.action.IndexAction.<clinit>(IndexAction.java:47)
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
java.lang.reflect.Constructor.newInstance(Unknown Source)
java.lang.Class.newInstance(Unknown Source)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:123)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:154)
com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:143)
com.opensymphony.xwork2.ObjectFactory.buildAction(ObjectFactory.java:113)
com.opensymphony.xwork2.DefaultActionInvocation.createAction(DefaultActionInvocation.java:275)
com.opensymphony.xwork2.DefaultActionInvocation.init(DefaultActionInvocation.java:365)
com.opensymphony.xwork2.DefaultActionInvocation.access$000(DefaultActionInvocation.java:38)
com.opensymphony.xwork2.DefaultActionInvocation$1.doProfiling(DefaultActionInvocation.java:83)
com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455)
com.opensymphony.xwork2.DefaultActionInvocation.<init>(DefaultActionInvocation.java:74)
com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:189)
org.apache.struts2.impl.StrutsActionProxyFactory.createActionProxy(StrutsActionProxyFactory.java:41)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:494)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:419)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.29 logs.

lib文件夹里就以下几个jar包：
commons-logging-1.0.4.jar
freemarker-2.3.8.jar
ognl-2.6.11.jar
sqljdbc4.jar
struts2-core-2.0.11.jar
xwork-2.0.4.jar

应该是数据库没有连接成功。请问您的SQL Server 2005数据库的登录用户是否为sa 密码为空，也就是没有密码。
另外，SQL Server的服务名是否为localhost？SQL Server配置管理器中的TCP/IP协议是否启用，并且设置的端口号是否全是1433？