Headache,please help me !

Question

I make a java program to visit a sqlserver 2000 database ,I download the SQL Server 2000 Driver for JDBC
,install,and set the classpath like "CLASSPATH=.;c:\Microsoft SQL Server 2000 Driver for JDBC\lib\msbase.jar;c:\Microsoft SQL Server 2000 Driver for JDBC\lib\msutil.jar;c:\Microsoft SQL Server 2000 Driver for JDBC\lib\mssqlserver.jar ".
when I register the driver to tells the JDBC driver manager which driver to load by using the below word
"Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");"
but fail!the program cannot find the driver!
why?
This is my program
JDBCDemo.java
import java.sql.*;
public class JDBCDemo
     public static void main(String[] args)
          Database db=new Database();
          db.connect();
          String sql="select * from book";
          String[] col={"bookID","bookName"};
          try
          db.execute(sql);
          while(db.rs.next())
               String temp=db.rs.getString(col[1]);
               System.out.println(temp+'\t');
          }catch(Exception e)
               System.out.println("resultset are error:"+e.getMessage());
          db.close();
class Database
          public Connection conn;
          public Statement stmt;
          public ResultSet rs=null;
          public Database()
          public boolean connect()
               try
                    Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
               }catch(ClassNotFoundException e)
                    System.out.println("Can not find the driver:"+e.getMessage());
               try
                    String ul="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=bookshop";
                    String user="sa";
                    String password="";
                    conn=DriverManager.getConnection(ul,user,password);
                    stmt=conn.createStatement();
               }catch(Exception e)
                    System.out.println("connect db error:"+e.getMessage());
                    return false;
               return true;
          public boolean execute(String s) throws Exception
               try
               rs=stmt.executeQuery(s);
               }catch(Exception e)
                    System.out.println("execute db error:"+e.getMessage());
                    return false;
               return true;
          public void close()
               try{
               stmt.close();
               conn.close();
               }catch(SQLException se)
                    System.out.println("close db error:"+se.getMessage());
who can tell me the reason and help me solve the problem?

Answer 1

Thank you very much ,but when I change the classpath.the problem turn to
Exception in thread "main" java.lang.NoClassDefFoundError: com/microsoft/jdbc/ba
se/BaseDriver
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:12
4)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:164)
at Database.connect(JDBCDemo.java:40)
at JDBCDemo.main(JDBCDemo.java:9)
why?