dbbean.java

在线判作业系统

package teachmanage.DB_management;

/**
  文件：access_bean.java
  说明：访问数据库的组件类
 **/

import java.sql.*;

public class DBbean {
    //声明驱动程序
    //String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
    String driver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
    //声明数据库的连接串
   // String url = "jdbc:odbc:test";
    // String url = "jdbc:odbc:TeachManage";
    String url = "jdbc:microsoft:sqlserver://192.168.1.55:1433;DatabaseName = TeachManage";
    String user = "sa";
    String pwd = "platform";
    // 声明连接接口
    Connection con = null;
    //声明语句对象
    Statement stmt = null;
    //声明结果集
    ResultSet rs = null;
    //类的构造方法
    public DBbean()  {
        //加载驱动程序
       try
          {
              Class.forName(driver);
          }catch (ClassNotFoundException e)
          {
              e.getStackTrace();
          }
        //建立与数据库的连接
        try
        {
            con = DriverManager.getConnection(url, user, pwd);
            stmt = con.createStatement();
        }catch(SQLException s)
        {
            s.getMessage();
            System.out.println(s);
        }
        //建立语句对象

    }

    //执行指定的select语句
    public ResultSet executeSelect(String sql) {
        //设置结果集为空
        rs = null;
        System.out.println(sql);
        //通过语句对象执行指定的SQL语句，得到结果集
        try
        {
            rs = stmt.executeQuery(sql);
        }
        catch(SQLException q)
                {
                 q.getMessage();
                System.out.println(q);
        }

        //返回结果集
        System.out.println(rs);
         return rs;
    }

    //执行指定的DML语句
    public int executeDML(String sql) throws SQLException {
       return stmt.executeUpdate(sql);
    }

    public void close()
    {
        try{
            if(con!=null)
                con.close();
        }catch(Exception e){}
        try{
            if(stmt!=null)
                stmt.close();
        }catch(Exception e){}
        try{
            if(rs!=null)
                rs.close();
        }catch(Exception e){}
    }
}