Eclipse做的系统运行有错误，是servlet的问题么？

type Exception report

message

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

exception

java.lang.NullPointerException
com.sccp.petsystem.service.LoginService.validateLogin(LoginService.java:23)
com.sccp.petsystem.servlet.LoginServlet.doPost(LoginServlet.java:44)
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

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what what???
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java.lang.NullPointerException
com.sccp.petsystem.service.LoginService.validateLogin(LoginService.java:23)
com.sccp.petsystem.servlet.LoginServlet.doPost(LoginServlet.java:44)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

看一下你写的servlet吧.

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空指针错误``
有对象没被实力化就被使用了

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恩我同意楼上的看法，应该是空指针异常。你检查以下是否又地方没有实例化。

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