opendata.java~4~

system1为用户注册模块 system2为在线聊天系统 system3为在线投票系统 system4为在线考试系统 system5为新闻发布模块

package database;
import java.sql.*;

public class opendata {
    private Connection con;
    private ResultSet rs;
    public static Connection getConnection() throws SQLException {
        try {
            Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
        } catch (ClassNotFoundException ex) {
            //ex.printStackTrace();
            //return null;
             System.out.println(ex);
        }
        return DriverManager.getConnection(
            "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=questionnaire","sa","");
    }

    public ResultSet executeQuery(String sql)   {
      try {
        con = opendata.getConnection();
        Statement statement = con.createStatement();
        rs = statement.executeQuery(sql);
    }
    catch(SQLException ex)
    {
        System.out.println(ex);
    }
    return rs;
   }

   public int executeUpdate(String sql)
  {
      int count = 0;
      Statement stmt = null;
      try
      {
          con = opendata.getConnection();
          stmt = con.createStatement();
          count = stmt.executeUpdate(sql);
      }
      catch(SQLException ex)
      {
      }
      finally
      {
          try
          {
              if(stmt != null)
                  stmt.close();
              if(con != null)
                  con.close();
          }
          catch(SQLException ex)
          {
              System.err.print(ex);
          }
      }
      return count;
  }

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