op_homework.java

用jsp实现的在线教学系统

package grad.util.homework;

import java.util.*;
import java.sql.*;
import grad.util.DataBase;

public class op_homework {
  public op_homework() {
  }
  /**
   * 查看指定课程所发布的全部作业
   * @param sourseid
   * @return
   */
  public ArrayList getAllHomeworkPub(String sourseid)
{
     Connection conn=null;
     Statement st=null;
     ResultSet rs=null;
     String sql ="select * from t_homework where course_code='"+sourseid+"' and type=1";
     ArrayList al=new ArrayList();
     try{
       DataBase ds = new DataBase();
       conn = ds.conn;
       st = conn.createStatement();
       rs = st.executeQuery(sql);
       while (rs.next()) {
          homework cs=new homework();
          cs.setid(rs.getInt(1));
          cs.settitle(rs.getString(2));
          cs.setlink(rs.getString(3));
          cs.setdate(rs.getString(4));
          cs.settype(rs.getString(5));
          cs.setcourse_code(rs.getString(6));
          cs.setuser_id(rs.getString(7));
          al.add(cs);
       }
       return al;
     }catch(Exception e){System.out.println(e.getMessage());return null;}

    }
    /**
     * 查询指定课程作业 全部学生提交的作业
     * @param sourseid
     * @return
     */
public ArrayList getAllHomeworkCommit(String sourseid)
{
     Connection conn=null;
     Statement st=null;
     ResultSet rs=null;
     String sql ="select * from t_homework where course_code='"+sourseid+"' and type=2 order by user_id desc";
     ArrayList al=new ArrayList();
     try{
       DataBase ds = new DataBase();
       conn = ds.conn;
       st = conn.createStatement();
       rs = st.executeQuery(sql);
       while (rs.next()) {
          homework cs=new homework();
          cs.setid(rs.getInt(1));
          cs.settitle(rs.getString(2));
          cs.setlink(rs.getString(3));
          cs.setdate(rs.getString(4));
          cs.settype(rs.getString(5));
          cs.setcourse_code(rs.getString(6));
          cs.setuser_id(rs.getString(7));
          cs.setstatus(rs.getString(8));
          al.add(cs);
       }
       return al;
     }catch(Exception e){System.out.println(e.getMessage());return null;}

    }
    /**
     * 查询学生为某门课程提交的全部作业答案
     * @param sourseid
     * @param stuentid
     * @return
     */
public ArrayList getAllHomeworkCommitBystu(String sourseid,String stuentid)
{
     Connection conn=null;
     Statement st=null;
     ResultSet rs=null;
     String sql ="select * from t_homework where course_code='"+sourseid+"' and type=2 and user_id='"+stuentid+"'";

     ArrayList al=new ArrayList();
     try{
       DataBase ds = new DataBase();
       conn = ds.conn;
       st = conn.createStatement();
       rs = st.executeQuery(sql);
       while (rs.next()) {
          homework cs=new homework();
          cs.setid(rs.getInt(1));
          cs.settitle(rs.getString(2));
          cs.setlink(rs.getString(3));
          cs.setdate(rs.getString(4));
          cs.settype(rs.getString(5));
          cs.setcourse_code(rs.getString(6));
          cs.setuser_id(rs.getString(7));
          cs.setstatus(rs.getString(8));
          al.add(cs);
       }
       return al;
     }catch(Exception e){System.out.println(e.getMessage());return null;}

    }
    /**
     * 添加作业 老师发布的作业 或者学生为作业提交的答案
     * @param rs
     */
    public void addHomework(homework rs)
      {
        Connection conn=null;
       Statement st=null;
       String sql="insert into t_homework(title,link,date,type,course_code,user_id)values("+
                  " '"+rs.gettitle()+"',"+
                  " '"+rs.getlink()+"',"+
                  " getdate(),"+
                  " '"+rs.gettype()+"',"+
                  " '"+rs.getcourse_code()+"',"+
                  " '"+rs.getuser_id()+"')";
              System.out.println(sql);
       try{
         DataBase ds = new DataBase();
         conn = ds.conn;
         st = conn.createStatement();
         st.executeUpdate(sql);

       }catch(Exception e){System.out.println(e.getMessage());return ;}
      }
      /**
       * 老师删除已发布作业
       * @param id
       */
      public void delHomeWork(String id)
      {
        Connection conn=null;
      Statement st=null;
      String sql="delete from t_homework where id='"+id+"'";
             System.out.println(sql);
      try{
        DataBase ds = new DataBase();
        conn = ds.conn;
        st = conn.createStatement();
        st.executeUpdate(sql);

      }catch(Exception e){System.out.println(e.getMessage());return ;}

      }
      /**
       * 学生提交答案 当老师阅览过后 置状态位为2
       * @param id
       */
      public static void  updateHomeWorkSta(String id)
           {
             Connection conn=null;
           Statement st=null;
           String sql="update  t_homework set status='2' where id='"+id+"'";
                  System.out.println(sql);
           try{
             DataBase ds = new DataBase();
             conn = ds.conn;
             st = conn.createStatement();
             st.executeUpdate(sql);

           }catch(Exception e){System.out.println(e.getMessage());return ;}

           }

}