2020/12/07

选课系统的dao层

package Dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import java.sql.ResultSet;
import java.sql.SQLException;

import DBUtil.DBUtil;
import information.*;
public class Dao {

	public boolean tadd(information in) {
        String sql = "insert into text2(tid,tname,tsex,tlocation,tzc) values('"+ in.getTid() + "','"+ in.getTname() + "','" + in.getTsex() + "','" + in.getTlocation() + "','" + in.getTzc() +"')";
        System.out.println(sql);
        Connection conn = DBUtil.getConn();
        Statement state = null;
        boolean f = false;
        int a = 1;
         
        try {
            state = conn.createStatement();
            state.executeUpdate(sql);
        } catch (Exception e) {
            e.printStackTrace();
            a=0;
        } finally {
            DBUtil.close(state, conn);
        }
         
        if (a > 0) {
            f = true;
        }
        return f;
    }
	
	public boolean sadd(student s) {
        String sql = "insert into text3(sid,sname,ssex,sclass,szy) values('"+ s.getSid() + "','"+ s.getSname() + "','"+s.getSsex() + "','" + s.getSclass() + "','" + s.getSzy() +"')";
        Connection conn = DBUtil.getConn();
        Statement state = null;
        boolean f = false;
        int a = 1;
         
        try {
            state = conn.createStatement();
            state.executeUpdate(sql);
        } catch (Exception e) {
            e.printStackTrace();
            a=0;
        } finally {
            DBUtil.close(state, conn);
        }
         
        if (a > 0) {
            f = true;
        }
        return f;
	}
	
	public boolean classadd(kecheng in) {
        String sql = "insert into class(kid,kname,knumber,kteacher) values('"+ in.getKid()+ "','"+ in.getKname() + "','" + in.getKnumber() + "','" + in.getKteacher() +"')";
        System.out.println(sql);
        Connection conn = DBUtil.getConn();
        Statement state = null;
        boolean f = false;
        int a = 1;
         
        try {
            state = conn.createStatement();
            state.executeUpdate(sql);
        } catch (Exception e) {
            e.printStackTrace();
            a=0;
        } finally {
            DBUtil.close(state, conn);
        }
         
        if (a > 0) {
            f = true;
        }
        return f;
    }
	
	

    
    
public List<information> tcha (String m) {
		String sql="select * from text2 where ";
		if(m!="") {
				sql+="tname = '"+m+"'";		
		}
		System.out.println(sql);
		
		Connection conn = DBUtil.getConn();
		Statement state = null;
		
		ResultSet rs = null;
		List<information> list = new ArrayList<>();
		try {
			state = conn.createStatement();
			rs = state.executeQuery(sql);
			information bean = null;
			while (rs.next()) {
				String tid = rs.getString("tid");
                String tname = rs.getString("tname");
                String tsex = rs.getString("tsex");
                String tlocation=rs.getString("tlocation");
                String tzc = rs.getString("tzc");
                System.out.println(tid);
                bean=new information(tid,tname,tsex,tlocation,tzc);
				list.add(bean);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			DBUtil.close(state, conn);
		}
		return list;
		}
    
    public List<student> scha (String m) {
		String sql="select * from text3 where ";
		if(m!="") {
				sql+="sname = '"+m+"'";		
		}
		
		
		Connection conn = DBUtil.getConn();
		Statement state = null;
		
		ResultSet rs = null;
		List<student> list = new ArrayList<>();
		try {
			state = conn.createStatement();
			rs = state.executeQuery(sql);
			student bean = null;
			while (rs.next()) {
				String sid = rs.getString("sid");
                String sname = rs.getString("sname");
                String ssex = rs.getString("ssex");
                String sclass=rs.getString("sclass");
                String szy = rs.getString("szy");
                bean=new student(sid,sname,ssex,sclass,szy);
				list.add(bean);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			DBUtil.close(state, conn);
		}
		return list;
    }
    
    
    public boolean tsan(String x) {
    	
        String sql="delete from text2 where tname='"+x+"'";
        Connection conn = DBUtil.getConn();
        Statement state = null;
        boolean f = false;
        int a = 1;
         
        try {
            state = conn.createStatement();
            state.executeUpdate(sql);
        } catch (Exception e) {
            e.printStackTrace();
            a=0;
        } finally {
            DBUtil.close(state, conn);
        }
         
        if (a > 0) {
            f = true;
        }
        return f;
    }

    public boolean ssan(String x) {
    	
        String sql="delete from text3 where sname='"+x+"'";
        Connection conn = DBUtil.getConn();
        Statement state = null;
        boolean f = false;
        int a = 1;
         
        try {
            state = conn.createStatement();
            state.executeUpdate(sql);
        } catch (Exception e) {
            e.printStackTrace();
            a=0;
        } finally {
            DBUtil.close(state, conn);
        }
         
        if (a > 0) {
            f = true;
        }
        return f;
    }
}

package Servlet;
import java.util.List;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import Dao.Dao;

import information.*;

@WebServlet("/Servlet")
public class Servlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	
    public Servlet() {
        super();
        
    }
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		req.setCharacterEncoding("utf-8");
		String method = req.getParameter("method");
		if ("tadd".equals(method)) {
			tadd(req, resp);

		} 
		if ("sadd".equals(method)) {
			sadd(req, resp);
		}
		if ("classadd".equals(method)) {
			classadd(req, resp);
		}
		if ("tjudge".equals(method)) {
			tjudge(req, resp);
		}
		if ("sjudge".equals(method)) {
			sjudge(req, resp);
		}
		if ("cha".equals(method)) {
			cha(req, resp);
		}
		if ("tgai".equals(method)) {
			tgai(req, resp);
		}
		if ("sgai".equals(method)) {
			sgai(req, resp);
		}
		if ("save".equals(method)) {
			save(req, resp);
		}
		if ("ssave".equals(method)) {
			ssave(req, resp);
		}
	}   
    
	private void tadd(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		HttpSession session = req.getSession();

		
		
		String tid = req.getParameter("tid");
		String tname = req.getParameter("tname");
		String tsex = req.getParameter("tsex");
		String tlocation = req.getParameter("tlocation");
		String tzc = req.getParameter("tzc");
		
		session.setAttribute("tid",tid);
		session.setAttribute("tname",tname);
		session.setAttribute("tsex",tsex);
		session.setAttribute("tlocation",tlocation);
		session.setAttribute("tzc",tzc);
	        
		
		System.out.println(tid);
		System.out.println(tname);
		System.out.println(tsex);
		System.out.println(tlocation);
		System.out.println(tzc);
		information information = new information(tid,tname,tsex,tlocation,tzc);
		Dao dao =new Dao();
		boolean f=dao.tadd(information);
		System.out.println(f);
		if(f) {
			req.setAttribute("message", "添加成功！");
			req.getRequestDispatcher("face.jsp").forward(req,resp);
		} else {
			req.setAttribute("message", "添加失败！");
			req.getRequestDispatcher("tadd.jsp").forward(req,resp);
		}
	}
    
    private void sadd(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		String sid = req.getParameter("sid");
		String sname = req.getParameter("sname");
		String ssex = req.getParameter("ssex");
		String sclass = req.getParameter("sclass");
		String szy = req.getParameter("szy");
		student student=new student(sid,sname,ssex,sclass,szy);
		Dao dao =new Dao();
		boolean f=dao.sadd(student);
		System.out.println(f);
		if(f) {
			req.setAttribute("message", "添加成功！");
			req.getRequestDispatcher("face.jsp").forward(req,resp);
		} else {
			req.setAttribute("message", "添加失败！");
			req.getRequestDispatcher("sadd.jsp").forward(req,resp);
		}
	}
    
    private void classadd(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");

		HttpSession session = req.getSession();
		
		String kid = req.getParameter("kid");
		String kname = req.getParameter("kname");
		String knumber= req.getParameter("knumber");
		String kteacher = (String) session.getAttribute("tname");
		
		System.out.println(kid);
		kecheng kecheng = new kecheng(kid,kname,knumber,kteacher);
		Dao dao =new Dao();
		boolean f=dao.classadd(kecheng);
		System.out.println(f);
		if(f) {
			req.setAttribute("message", "添加成功！");
			req.getRequestDispatcher("face.jsp").forward(req,resp);
		} else {
			req.setAttribute("message", "添加失败！");
			req.getRequestDispatcher("teacher.jsp").forward(req,resp);
		}
	}
    
    private void tjudge(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		HttpSession session = req.getSession();
	      
		String tid = req.getParameter("tid");
		String tname = req.getParameter("tname");
		
		session.setAttribute("tid",tid);
		session.setAttribute("tname",tname);
		Dao dao=new Dao();

		List<information> holds = dao.tcha((String) session.getAttribute("tname"));
		req.setAttribute("holds", holds);
		req.getRequestDispatcher("teacher.jsp").forward(req,resp);
    }
    
    private void save(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		HttpSession session = req.getSession();
	    
		Dao dao=new Dao();

		List<information> holds = dao.tcha((String) session.getAttribute("tname"));
		req.setAttribute("holds", holds);
		req.getRequestDispatcher("tmodify.jsp").forward(req,resp);
    }
    
    private void ssave(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		HttpSession session = req.getSession();
	    
		Dao dao=new Dao();

		List<student> holds = dao.scha((String) session.getAttribute("sname"));
		req.setAttribute("holds", holds);
		req.getRequestDispatcher("smodify.jsp").forward(req,resp);
    }
    
    private void sjudge(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
		req.setCharacterEncoding("utf-8");
		HttpSession session = req.getSession();
	      
		String sid = req.getParameter("sid");
		String sname = req.getParameter("sname");
		Dao dao=new Dao();
		
		session.setAttribute("sid",sid);
		session.setAttribute("sname",sname);
		System.out.println(sname);
		List<student> holds = dao.scha(sname);
		req.setAttribute("holds", holds);
		req.getRequestDispatcher("student.jsp").forward(req,resp);
    }
    private void cha(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    	req.setCharacterEncoding("utf-8");	
    	HttpSession session = req.getSession();
		Dao dao=new Dao();
		String k=(String) session.getAttribute("tname");
		System.out.println(k);
		List<information> holds = dao.tcha(k);
		req.setAttribute("holds", holds);
		req.getRequestDispatcher("teacher.jsp").forward(req,resp);
		
    }
    
    private void tgai(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    	req.setCharacterEncoding("utf-8");
    	
    	String tid = req.getParameter("tid");
		String tname = req.getParameter("tname");
		String tsex = req.getParameter("tsex");
		String tlocation = req.getParameter("tlocation");
		String tzc = req.getParameter("tzc");
		
		System.out.println(tid);
		System.out.println(tname);
		System.out.println(tsex);
		System.out.println(tlocation);
		System.out.println(tzc);
		
		information information = new information(tid,tname,tsex,tlocation,tzc);
		Dao dao =new Dao();
	
		dao.tsan(tname);
		dao.tadd(information);
		req.getRequestDispatcher("teacher.jsp").forward(req,resp);
    }
    
    private void sgai(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    	req.setCharacterEncoding("utf-8");
    	String sid = req.getParameter("sid");
		String sname = req.getParameter("sname");
		String ssex = req.getParameter("ssex");
		String sclass = req.getParameter("sclass");
		String szy = req.getParameter("szy");
		student student=new student(sid,sname,ssex,sclass,szy);
		Dao dao =new Dao();
		HttpSession session = req.getSession();
		String k=(String) session.getAttribute("sname");
		dao.ssan(k);
		dao.sadd(student);
		req.getRequestDispatcher("student.jsp").forward(req,resp);
    }


}

 这里是servlet层