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java.lang.NullPointerException问题
摘要: java.lang.NullPointerException问题
大家帮我看看运行时出现了这个错误， 这是为什么呢
org.apache.jasper.JasperException: Exception in JSP: /cook/login.jsp:6
3: String UserName = "", UserEMail = "", LoginDate = "";
4: Cookie temp = null;
5: Cookie[] cookies = request.getCookies();
6: int cookielen = cookies.length;
7:
8: for (int i = 0; i < cookielen; i++) {
9: temp = cookies[i];
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause
java.lang.NullPointerException
org.apache.jsp.cook.login_jsp._jspService(login_jsp.java:48)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
<%@ page language="java" contentType="text/html;charset=gb2312"%>
<%
String UserName = "", UserEMail = "", LoginDate = "";
Cookie temp = null;
Cookie[] cookies = request.getCookies();
int cookielen = cookies.length;
for (int i = 0; i < cookielen; i++) {
temp = cookies[i];
if (temp.getName().equals("Name")) {
UserName = temp.getValue();
} else if (temp.getName().equals("E_Mail")) {
UserEMail = temp.getValue();
} else if (temp.getName().equals("LoginDate")) {
LoginDate = temp.getValue();
}
}
int tmplen = LoginDate.length();
boolean FirstLogin;
if (tmplen != 0) {
FirstLogin = false;
} else {
FirstLogin = true;
}
%>
HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<head>