1.数据库建表

三张表：学生（id,名字，班级，教员，爱好）

? ? ? ? ? ? ? ?班级（id,名字）

、? ? ? ? ? ?教员?（id,名字）

2.项目构造

?创建Web项目，导入架包，数据库帮助包，实体类，Servlet类，接口类，实现接口类(dao方法类)

?3.成果展示

1.主界面

主界面代码：

<%@ page language="java" contentType="text/html; charset=utf-8"
	pageEncoding="utf-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>主界面</title>
<style type="text/css">
table, tr {
	border-collapse: collapse;
}

td {
	text-align: center;
}
</style>
</head>
<body>




	<table border="" width="1200" height="400px" align="center">
		<tr>
			<td colspan="6">
				<form action="key.do">
					教员: <select name="teacher" class="select">
						<option value="null">--选择教员--</option>
						<c:forEach var="t" items="${ allt }">
							<option value="${ t.tname }" ${ t.tname==teacher?"selected":"" }>
								${ t.tname }</option>
						</c:forEach>
					</select> 班级: <select name="class1" class="select">
						<option value="null">--选择班级--</option>
						<c:forEach var="c" items="${ allc }">
							<option value="${ c.cname }" ${ c.cname==class1?"selected":""}>
								${ c.cname }</option>
						</c:forEach>
					</select> 学生爱好: <input type="checkbox" name="shobby" value="篮球"
						<c:forEach var="i" items="${ alls }">
                      <c:if test="${ i.shobby=='篮球' }"> checked</c:if></c:forEach>>篮球
					<input type="checkbox" name="shobby" value="足球"
						<c:forEach var="i" items="${ alls }">
                      <c:if test="${ i.shobby=='足球' }"> checked</c:if></c:forEach>>足球
					<input type="checkbox" name="shobby" value="唱歌"
						<c:forEach var="i" items="${ alls }">
                      <c:if test="${ i.shobby=='唱歌' }"> checked</c:if></c:forEach>>唱歌
					<input type="checkbox" name="shobby" value="跳舞"
						<c:forEach var="i" items="${ alls }">
                      <c:if test="${ i.shobby=='跳舞' }"> checked</c:if></c:forEach>>跳舞
					<button>查询</button>

				</form>
				<button onclick="location.href='Add.jsp'">增加学生</button>
			</td>
		</tr>


		<tr>
			<td>学生id</td>
			<td>学生名字</td>
			<td>学生班级</td>
			<td>学生教员</td>
			<td>学生爱好</td>
			<td>操作</td>
		</tr>
		<c:forEach var="i" items="${alls }">
			<tr>
				<td>${ i.sid }</td>
				<td>${ i.sname }</td>
				<td>${ i.sclass }</td>
				<td>${ i.steacher }</td>
				<td>${ i.shobby }</td>
				<td><a href="get.do?ssid=${ i.sid }">修改</a> <a
					href="del.do?ssid=${i.sid }">删除</a></td>
			</tr>
		</c:forEach>
	</table>



</body>
</html>

2.模糊查询

?3.增加界面

增加成功后，界面弹出增加成功?

3 修改界面（要有原有数据）

修改完成弹出修改成功?

?dao方法代码：

package com.sdao;

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

import com.entity.Student;
import com.student.impl.IStudentDao;
import com.util.DBHerpre;
/**
 * 学生数据库操作类
 * @author 
 *
 */
public class StudentDao implements IStudentDao {

	private Connection con;
	private PreparedStatement ps;
	private ResultSet rs;

	/**
	 * 增加
	 */
	public int add(Student s) {
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("insert into tb_Student values(?,?,?,?)");
			ps.setString(1, s.getSname());
			ps.setString(2, s.getSclass());
			ps.setString(3, s.getSteacher());
			ps.setString(4, s.getShobby());
			return ps.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return 0;
	}

	/**
	 * 删除
	 */
	public int del(int sid) {
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("delete tb_Student where sid=?");
			ps.setInt(1, sid);
			return ps.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return 0;
	}

	/**
	 * 修改
	 */
	public int upd(Student s) {
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("update tb_Student set sname=?,sclass=?,steacher=?,shobby=? where sid=?");
			ps.setString(1, s.getSname());
			ps.setString(2, s.getSclass());
			ps.setString(3, s.getSteacher());
			ps.setString(4, s.getShobby());
			ps.setInt(5, s.getSid());
			return ps.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return 0;
	}

	/**
	 * 查询全部
	 */
	public List<Student> getAll() {
		List<Student> list = new ArrayList<Student>();
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("select * from tb_Student");
			rs=ps.executeQuery();
			while(rs.next()) {
				Student s = new Student();
				s.setSid(rs.getInt(1));
				s.setSname(rs.getString(2));
				s.setSclass(rs.getString(3));
				s.setSteacher(rs.getString(4));
				s.setShobby(rs.getString(5));
				list.add(s);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return list;
	}

	/**
	 * 根据id查询单个
	 */
	public Student getId(int sid) {
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("select * from tb_Student where sid=?");
			ps.setInt(1, sid);
			rs=ps.executeQuery();
			if(rs.next()) {
				Student s = new Student();
				s.setSid(rs.getInt(1));
				s.setSname(rs.getString(2));
				s.setSclass(rs.getString(3));
				s.setSteacher(rs.getString(4));
				s.setShobby(rs.getString(5));
				return s;
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return null;
	}

	/**
	 * 模糊查询
	 */
	public List<Student> getMo(String sclass, String steacher, String shobby) {
		List<Student> list = new ArrayList<Student>();
		try {
			con=DBHerpre.getCon();
			ps=con.prepareStatement("select * from tb_Student where sclass like ? and steacher like ? and shobby like ?");
			
			ps.setString(1, "%"+sclass+"%");
			ps.setString(2, "%"+steacher+"%");
			ps.setString(3, "%"+shobby+"%");
			rs=ps.executeQuery();
			while(rs.next()) {
				Student s = new Student();
				s.setSid(rs.getInt(1));
				s.setSname(rs.getString(2));
				s.setSclass(rs.getString(3));
				s.setSteacher(rs.getString(4));
				s.setShobby(rs.getString(5));
				list.add(s);
			}
			return list;
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return null;
	}

	
	
}

package com.cdao;

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

import com.cclass.impl.IClassDao;
import com.entity.Class;
import com.util.DBHerpre;
/**
 * 班级数据库操作包
 * @author zjjt
 *
 */
public class Clasa1Dao implements IClassDao{
	
	private Connection con;
	private PreparedStatement ps;
	private ResultSet rs;

	/**
	 * 查询所有班级
	 */
	public List<Class> getCname() {
		List<Class> list = new ArrayList<Class>();
		try {
			con = DBHerpre.getCon();
			ps = con.prepareStatement("select * from tb_Class");
			rs = ps.executeQuery();
			while(rs.next()) {
				Class c = new Class();
				c.setCid(rs.getInt(1));
				c.setCname(rs.getString(2));
				list.add(c);
			}
			return list;
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return null;
	}

}

package com.tdao;

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

import com.entity.Teacher;
import com.teacher.impl.ITeacherDao;
import com.util.DBHerpre;
/**
 * 教员数据库操作包
 * @author zjjt
 *
 */
public class TeacherDao implements ITeacherDao{

	private Connection con;
	private PreparedStatement ps;
	private ResultSet rs;
	
	/**
	 * 查寻所有老师的名字
	 */
	public List<Teacher> getTname() {
		List<Teacher> list = new ArrayList<Teacher>();
		try {
			con = DBHerpre.getCon();
			ps = con.prepareStatement("select * from tb_Teacher");
			rs = ps.executeQuery();
			while(rs.next()) {
				Teacher t = new Teacher();
				t.setTid(rs.getInt(1));
				t.setTname(rs.getString(2));
				list.add(t);
			}
			return list;
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHerpre.myClose(con, ps, rs);
		}
		return null;
	}
	
	
	
}

到这里就结束了，我依旧是那个学IT的小学生?

欢迎大佬指点?