javabean问题
userinfo.java文件
package   com.bxgl.zaly;
public   class   userinfo
{
private   String   username;
private   String   password;

public   String   getUsername()
{
return   username;
}

public   String   getPassword()
{
return   password;
}


public   void   setUsername(String   username)
{
this.username=username;
}
public   void   serPassword(String   password)
{
this.password=password;
}

}

userregist.java
package   com.bxgl.zaly;
import   java.sql.*;


public   class   userregist
{
Connection   conn=null;
private   userinfo   usin;

public   userregist()
{
try
{
Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver ");
String   url= "jdbc:odbc:driver={Microsoft   Access   Driver   (*.mdb)};DBQ=data\bxgl.mdb ";
conn=DriverManager.getConnection(url);
}
catch   (Exception   e)
{
e.printStackTrace();
}
}

public   void   setUsin(userinfo   usin)
{
this.usin=usin;
}

public   void   regist()throws   Exception
{
String   sql= "insert   into   user(username,password)   values(?,?) ";
try
{
PreparedStatement   pstmt=conn.prepareStatement(sql);
pstmt.setString(1,usin.getUsername());
pstmt.setString(2,usin.getPassword());
pstmt.executeUpdate();
}
catch   (Exception   e)
{
e.printStackTrace();
throw   e;
}
}
}
newuser.jsp文件
<%@   page   language= "java "   contentType= "text/html;charset=gb2312 "   import= "com.bxgl.zaly.* "%>

<jsp:useBean   id= "usin "   class= "com.bxgl.zaly.userinfo "   scope= "page ">
<jsp:setProperty   name= "usin "   property= "* "/>
</jsp:useBean>

<jsp:useBean   id= "regist "   class= "com.bxgl.zaly.userregist "   scope= "page "/>

<%
regist.setUsin(usin);
regist.regist();
out.println( "注册成功 ");
%>
报错内容
Exception   report

message  

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

exception  

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:372)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root   cause  

java.lang.NullPointerException
com.bxgl.zaly.userregist.regist(userregist.java:34)
org.apache.jsp.newuser_jsp._jspService(newuser_jsp.java:72)
org.apache.jasper.runtime.HttpJspB