dbmanager.java

学生管理系统

package student;

import java.sql.*;
import java.util.*;
public class dbmanager {
private Connection con=null;
private Statement conn=null;
private ResultSet rs=null;

    static
   {
    try {
        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    } catch (Exception ex) {
        System.out.println(ex);
    }

   }
   //执行查询语句

  public ResultSet exeselect(String sql)
   {
       try {

           con=DriverManager.getConnection("jdbc:odbc:test","sa","");
           conn=con.createStatement();
           rs=conn.executeQuery(sql);
           } catch (Exception ex) {
               System.out.println(ex);
         }
         if(rs==null)
         {
         return rs=null;

         }

        return rs;
   }

   //查询时,关闭数据库连接
 public void closeAll()
    {
    try {
        rs.close();
        conn.close();
        con.close();
    } catch (Exception ex) {
    System.out.println(ex);
    }
    }
    //用于数据库增加\更新\删除操作

    public int exeupdate(String sql)
    {
      int rows=-1;
      try {
          con=DriverManager.getConnection("jdbc:odbc:test","sa","");
          conn=con.createStatement();
          rows=conn.executeUpdate(sql);

      } catch (Exception ex) {
          System.out.println(ex);
      }finally
      {
          try {
         conn.close();
         con.close();
          } catch (Exception ex) {

          }


      }
      if(rows>0)
      {
         return rows;
      }
      else{
       return rows=-1;
      }

    }






}