初学者：请帮忙看看问题出现在哪里，，关于tomcat+jsp的。
HTTP Status 500 -

--------------------------------------------

type Exception report

message

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

exception

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:372)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root cause

java.lang.NullPointerException
org.apache.jsp.login_jsp._jspService(login_jsp.java:72)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.



[解决办法]
最基本的错误，你照着你所做的例子再重新做一下试试看
[解决办法]
jsp页面错误
[解决办法]
看看你页面配置有没有问题，连接正不正常，这个不算大问题
[解决办法]
到%tomcat%\work\Catalina\localhost\目录下面找到你的那个工程。
然后打开login_jsp.java文件。看看72行是什么，你的错误就在那里！
[解决办法]
java.lang.NullPointerException
login_jsp的72行代码出现空指针异常.
我的异常网推荐解决方案：The server encountered an internal error () that prevented it from fulfilling this request.,http://www.myexception.cn/java-web/317.html