<%@ page contentType="text/html; charset=gb2312" %>
<%@ page import="java.sql.*"%>
<%@ page session="true" %>
<% request.setCharacterEncoding("GB2312"); %>
<html >
<head>
<title>登录检查</title>
</head>
<body bgcolor="#ccccff">
<%
String regName=(String)request.getParameter("username");
regName=regName.trim();
String regPassword=(String)request.getParameter("password");
regPassword=regPassword.trim();
String regEmail=(String)request.getParameter("useremail");
regEmail=regEmail.trim();
String regsex=(String)request.getParameter("sex");
regsex=regsex.trim();
String regbrith=(String)request.getParameter("birth_year")+"-"+(String)request.getParameter("birth_month")+"-"+(String)request.getParameter("birth_day");
regbrith=regbrith.trim();
%>
<jsp:useBean id="reg" scope="page" class="microblog.chatreg"></jsp:useBean>
<%
String sql="selsct * from chatreg where username='"+regName+"'";
ResultSet rs=reg.executeQuery(sql);
if(rs.next()){
rs.close();
out.println("<center><h2>对不起,你的大名已经存在"+"</h2></center><br>");
out.println("<center><a href=\"register.jsp\">重新注册</a></center><br>");
}
else{
String strSQL="insert into chatreg values('"+regName+"','"+regPassword+"','"+regEmail+"','"+regsex+"','"+regbrith+"')";
if(reg.executeUpdate(strSQL)){
out.println("<center><h2 color=red>恭喜你注册成功,成为我们的一员"+"</center></h2><br>");
out.println("<center><a href=\"in.jsp\">进入微博"+"</a></center>");
}
else{
out.println("<center><h2 color=red>对不起,注册失败!"+"</h2></center><br><br>");
out.println("<center><a href=\"register.jsp\">返回</a></center>");
}
}
reg.close();
%>
</body>
</html>
错误提示:
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root causejava.lang.NullPointerException
org.apache.jsp.chatregcof_jsp._jspService(chatregcof_jsp.java:91)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
<%@ page import="java.sql.*"%>
<%@ page session="true" %>
<% request.setCharacterEncoding("GB2312"); %>
<html >
<head>
<title>登录检查</title>
</head>
<body bgcolor="#ccccff">
<%
String regName=(String)request.getParameter("username");
regName=regName.trim();
String regPassword=(String)request.getParameter("password");
regPassword=regPassword.trim();
String regEmail=(String)request.getParameter("useremail");
regEmail=regEmail.trim();
String regsex=(String)request.getParameter("sex");
regsex=regsex.trim();
String regbrith=(String)request.getParameter("birth_year")+"-"+(String)request.getParameter("birth_month")+"-"+(String)request.getParameter("birth_day");
regbrith=regbrith.trim();
%>
<jsp:useBean id="reg" scope="page" class="microblog.chatreg"></jsp:useBean>
<%
String sql="selsct * from chatreg where username='"+regName+"'";
ResultSet rs=reg.executeQuery(sql);
if(rs.next()){
rs.close();
out.println("<center><h2>对不起,你的大名已经存在"+"</h2></center><br>");
out.println("<center><a href=\"register.jsp\">重新注册</a></center><br>");
}
else{
String strSQL="insert into chatreg values('"+regName+"','"+regPassword+"','"+regEmail+"','"+regsex+"','"+regbrith+"')";
if(reg.executeUpdate(strSQL)){
out.println("<center><h2 color=red>恭喜你注册成功,成为我们的一员"+"</center></h2><br>");
out.println("<center><a href=\"in.jsp\">进入微博"+"</a></center>");
}
else{
out.println("<center><h2 color=red>对不起,注册失败!"+"</h2></center><br><br>");
out.println("<center><a href=\"register.jsp\">返回</a></center>");
}
}
reg.close();
%>
</body>
</html>
错误提示:
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root causejava.lang.NullPointerException
org.apache.jsp.chatregcof_jsp._jspService(chatregcof_jsp.java:91)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jsp.chatregcof_jsp._jspService(chatregcof_jsp.java:91)空指针异常
估计应该是这一排里面的问题:
String regName=(String)request.getParameter("username");
regName=regName.trim();
String regPassword=(String)request.getParameter("password");
regPassword=regPassword.trim();
String regEmail=(String)request.getParameter("useremail");
regEmail=regEmail.trim();
String regsex=(String)request.getParameter("sex");
regsex=regsex.trim();
String regbrith=(String)request.getParameter("birth_year")+"-"+(String)request.getParameter("birth_month")+"-"+(String)request.getParameter("birth_day");
regbrith=regbrith.trim();
如果request.getParameter所得到的内容是 null,那么你后面调用的相当于是:
null.trim();
必然是以失败而告终。
regName=regName.trim();
建议如下操作:
String regName=String.valueOf(request.getParameter("username"));
regName=regName.trim();//这里regName可能会出现显示字符null的情况
或者
Object oregname = request.getParameter("username");
String regName = (null != oregname)?String.valueOf(request.getParameter("username")).trim():"参数为空(这里写成参数为空时显示的值)";
String regName = (String)request.getParameter("username");
if(regName!=null){
regName = regName.trim();
}