at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:581)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
2011-5-25 12:49:24 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at org.apache.jsp.zhuce_jsp._jspService(zhuce_jsp.java:63)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="test.*,test.User.*"%>
<html>
<body>
<%
String id=request.getParameter("username");
out.println(id);
id=new String(id.getBytes("iso-8859-1"),"utf-8");
out.println(id);
String pwd=request.getParameter("password");
out.println(pwd);
UserDAO ud = new UserDAO();
if(ud.addUser(id,pwd)){
out.println("<script>alert('注册成功！');location.href='success.jsp';</script>");
}else{
out.println("<script>alert('注册失败！');location.href='zhuce.jsp';</script>");}
%>
</body>
</html>
package test;
import java.sql.*;
import test.User;
public class UserDAO {
//判断用户是否存在
public User getUser(String id,String pwd){
String sql="select * from dl where uname='"+id+"'and upwd='"+pwd+"'";
databaselinktest dblt=new databaselinktest();
ResultSet rs=null;
User user=null;
rs=dblt.executeQuery(sql);
try{
while(rs.next()){
int idn=rs.getInt(1);
String uname = rs.getString(2);
String upwd = rs.getString(3);
user = new User(idn,uname,upwd);
}
} catch (SQLException e) {
e.printStackTrace();
} finally{
dblt.Closeconn();
}
return user;
}
//添加用户信息
public boolean addUser(String id,String pwd){
String sql="insert into dl(userID,userPassWord) values(?,?)";
databaselinktest dblt = new databaselinktest();
Object[] pram={id,pwd};
int rows = dblt.executeUpdate(sql,pram);
if(rows>0){
return true;
}else{
return false;
}
}
}
哪位高手告诉我哪有空值 啊
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
2011-5-25 12:49:24 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at org.apache.jsp.zhuce_jsp._jspService(zhuce_jsp.java:63)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="test.*,test.User.*"%>
<html>
<body>
<%
String id=request.getParameter("username");
out.println(id);
id=new String(id.getBytes("iso-8859-1"),"utf-8");
out.println(id);
String pwd=request.getParameter("password");
out.println(pwd);
UserDAO ud = new UserDAO();
if(ud.addUser(id,pwd)){
out.println("<script>alert('注册成功！');location.href='success.jsp';</script>");
}else{
out.println("<script>alert('注册失败！');location.href='zhuce.jsp';</script>");}
%>
</body>
</html>
package test;
import java.sql.*;
import test.User;
public class UserDAO {
//判断用户是否存在
public User getUser(String id,String pwd){
String sql="select * from dl where uname='"+id+"'and upwd='"+pwd+"'";
databaselinktest dblt=new databaselinktest();
ResultSet rs=null;
User user=null;
rs=dblt.executeQuery(sql);
try{
while(rs.next()){
int idn=rs.getInt(1);
String uname = rs.getString(2);
String upwd = rs.getString(3);
user = new User(idn,uname,upwd);
}
} catch (SQLException e) {
e.printStackTrace();
} finally{
dblt.Closeconn();
}
return user;
}
//添加用户信息
public boolean addUser(String id,String pwd){
String sql="insert into dl(userID,userPassWord) values(?,?)";
databaselinktest dblt = new databaselinktest();
Object[] pram={id,pwd};
int rows = dblt.executeUpdate(sql,pram);
if(rows>0){
return true;
}else{
return false;
}
}
}
哪位高手告诉我哪有空值 啊
这块看下，你的那个zhuce_jsp页面第63行。。
zhuce_jsp.java:63看看63行是什么，从而找到空指针的原因
zhuce_jsp.java:63行2:你可调试跟踪一下。