这种错误怎么解决呢？
HTTP Status 500 -

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type Exception report

message

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

exception

java.lang.NullPointerException
Regist.doPost(Regist.java:26)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.13 logs.


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Apache Tomcat/6.0.13[code=HTML][/code]

[解决办法]
Regist.java:26行 有东西为null
[解决办法]
空指针异常嘛

有东东为空你就拿来用了
[解决办法]
在定义了这个变量

Java code

 ConnSql ConMySql = null;
[解决办法]
楼上正解！

java.lang.NullPointerException 空指针异常了！
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