infobean.java

自己写的一个网上选课系统 可能有些问题大家可以分享一下 用的是 ＪＳＰ ＋access数据库

package test;
import java.sql.*;
public class infoBean{
private String ab="sun.jdbc.odbc.JdbcOdbcDriver";
private String ac="JDBC:odbc:info.mdb";
Connection conn=null;
ResultSet rs=null;
Statement stmt;
public infoBean(){
try{
Class.forName(ab);}
catch(java.lang.ClassNotFoundException e){
System.out.println("infoBean():"+e.getMessage());}
}
public ResultSet executeQuery(String sql){
rs=null;
try{
conn=DriverManager.getConnection(ac);
 stmt=conn.createStatement();
rs = stmt.executeQuery(sql);}
catch(SQLException ex){
System.err.println("aq.executeQuery:"+ex.getMessage());}
return rs;
}
public void executeUpdate(String sql)
{stmt=null;
rs=null;
try{
conn=DriverManager.getConnection(ac);
stmt=conn.createStatement();
stmt.executeUpdate(sql);
stmt.close();
conn.close();}
catch(SQLException e1)
{System.err.println("executeUpdate:" + e1.getMessage()); }
}
public void closeStmt() 
{ 
try{ 
stmt.close(); 
} 
catch (SQLException e2) 
{ 
e2.printStackTrace(); 
} 
} 

public void closeConn() 
{ 
try{ 
conn.close(); 
} 
catch (SQLException e3) 
{ 
e3.printStackTrace(); 
} 
}
}