MVC实现登录,增删改查之数据展示:JSP的EL表达式

public class Student {
 private int sid;
 private String sname;
 private String sage;
 public int getSid() {
 return sid;
 }
 public void setSid(int sid) {
 this.sid = sid;
 }
 public String getSname() {
 return sname;
 }
 public void setSname(String sname) {
 this.sname = sname;
 }
 public String getSage() {
 return sage;
 }
 public void setSage(String sage) {
 this.sage = sage;
 }
 public Student() {
 super();
 }
 public Student(int sid, String sname, String sage) {
 super();
 this.sid = sid;
 this.sname = sname;
 this.sage = sage;
 }
 
}

public interface StudentDao {

 /**
 * 
 * @param tid
 * @return 学生对象
 * 根据老师id返回学生对象
 */
 public List getStudentBytid(int tid);
}

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import JDBCUtil.JDBCUtil;
import com.zr.dao.StudentDao;
import com.zr.model.Student;
public class StudentDaoImpl implements StudentDao{
 /**
 * 根据传入的老师id获取学生
 */
 public List getStudentBytid(int tid) {
 //定义学生对象集合students接收数据库返回
 List students = new ArrayList();
 //获取数据库连接
 Connection con=JDBCUtil.getConnection();
 //编写SQL语句
 StringBuffer sql=new StringBuffer("select * from student where tid=?");
 try {
 PreparedStatement pst=con.prepareStatement(sql.toString());
 pst.setInt(1, tid);
 //返回一个结果集
 ResultSet rs=pst.executeQuery();
 while (rs.next()) {
 //学生对象接收结果集的结果
 Student s=new Student();
 s.setSid(rs.getInt("sid"));
 s.setSname(rs.getString("sname"));
 s.setSage(rs.getString("sage"));
 students.add(s);
 }
 } catch (SQLException e) {
 e.printStackTrace(); 
 }
 return students;
 }

import java.util.List;
import com.zr.model.Student;
public interface searchService {
 /**
 * 查询服务
 * @param tid 通过老师ID
 * @return 学生对象所有信息
 */
public List getStudents(int tid);
}

import java.util.ArrayList;
import java.util.List;
import com.zr.dao.StudentDao;
import com.zr.daoIm.StudentDaoImpl;
import com.zr.model.Student;
import com.zr.service.searchService;
public class searchServiceImpl implements searchService{

 public List getStudents(int tid) {
 
 List students=new ArrayList();
 StudentDao studentDaoImpl =new StudentDaoImpl();
 students= studentDaoImpl.getStudentBytid(tid); 
 return students;
 }

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.zr.model.Student;
import com.zr.model.Teacher;
import com.zr.service.searchService;
import com.zr.serviceIm.searchServiceImpl;
public class SearchController extends HttpServlet {
 @Override
 protected void service(HttpServletRequest req, HttpServletResponse resp)
 throws ServletException, IOException {
 
 List students=new ArrayList();
 searchService sc=new searchServiceImpl();
 //获取存放在session中的teacher对象
 Teacher teacher=(Teacher) req.getSession().getAttribute("teacher");
 //获取老师ID
 int td= teacher.getTid();
 //根据老师id获取学生对象 
 students= sc.getStudents(td);
 
 //将students对象放入session中,前台用EL表达式获取值
 HttpSession session= req.getSession();
 session.setAttribute("students", students);
 req.getRequestDispatcher("main.jsp").forward(req, resp);
 }
 }

 
 selectStus
 com.zr.controller.SearchController
 
 
 selectStus
 /selectStus
 

 
 
 
 

 

 
学生编号
 
学生名
 
学生年龄
 
 
 

 
${student.sid}
 
${student.sname}
 
${student.sage}