商品信息系统 | 易学教程

entity层

package com.hjf.entity;

public class Course {

private int id;
private String name;
private String place;
private String guige;
private String number;

public int getId()
{
return id;
}

public void setId(int id)
{
this.id = id;
}

public String getName()
{
return name;
}

public void setName(String name)
{
this.name = name;
}

public String getPlace()
{
return place;
}

public void setPlace(String place)
{
this.place = place;
}

public String getGuige()
{
return guige;
}

public void setGuige(String guige)
{
this.guige = guige;
}

public String getNumber()
{
return number;
}

public void setNumber(String number)
{
this.number = number;
}

public Course() {}

public Course(int id, String name, String teacher, String classroom,String number) {
  this.id = id;
  this.name = name;
  this.place = place;
  this.guige = guige;
  this.number=number;
}

public Course(String name, String teacher, String classroom,String number) {
  this.name = name;
  this.place = place;
  this.guige = guige;
  this.number=number;
}

dao层

package com.hjf.dao;

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

import com.hjf.entity.Course;
import com.hjf.util.DBUtil;

/**
* 商品Dao
* Dao层操作数据
* @author L
*
*/
public class CourseDao {

/**
* 添加
* @param course
* @return
*/
public boolean add(Course course) {
  String sql = "insert into course(name, place, guige,number) values('" + course.getName() + "','" + course.getPlace() + "','" + course.getGuige() + "','" + course.getNumber()+"')";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  boolean f = false;
  int a = 0;

  try {
   state = conn.createStatement();
   state.executeUpdate(sql);
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(state, conn);
  }

  if (a > 0) {
   f = true;
  }
  return f;
}

/**
* 删除
*
* @param id
* @return
*/
public boolean delete (int id) {
  boolean f = false;
  String sql = "delete from course where id='" + id + "'";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  int a = 0;

  try {
   state = conn.createStatement();
   a = state.executeUpdate(sql);
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(state, conn);
  }

  if (a > 0) {
   f = true;
  }
  return f;
}

/**
* 修改
* @param name
* @param pass
*/
public boolean update(Course course) {
  String sql = "update course set name='" + course.getName() + "', place='" + course.getPlace() + "', guige='" + course.getGuige()+"', number='" + course.getNumber()
   + "' where id='" + course.getId() + "'";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  boolean f = false;
  int a = 0;

  try {
   state = conn.createStatement();
   a = state.executeUpdate(sql);
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(state, conn);
  }

  if (a > 0) {
   f = true;
  }
  return f;
}

/**
* 验证课程名称是否唯一
* true --- 不唯一
* @param name
* @return
*/
public boolean name(String name) {
  boolean flag = false;
  String sql = "select name from course where name = '" + name + "'";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  ResultSet rs = null;

  try {
   state = conn.createStatement();
   rs = state.executeQuery(sql);
   while (rs.next()) {
    flag = true;
   }
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(rs, state, conn);
  }
  return flag;
}

/**
* 通过ID得到类
* @param id
* @return
*/
public Course getCourseById(int id) {
  String sql = "select * from course where id ='" + id + "'";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  ResultSet rs = null;
  Course course = null;

  try {
   state = conn.createStatement();
   rs = state.executeQuery(sql);
   while (rs.next()) {
    String name = rs.getString("name");
    String place = rs.getString("place");
    String guige = rs.getString("guige");
    String number = rs.getString("number");
    course = new Course(id, name, place,guige,number);
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(rs, state, conn);
  }

  return course;
}

/**
* 通过name得到Course
* @param name
* @return
*/
public Course getCourseByName(String name) {
  String sql = "select * from course where name ='" + name + "'";
  Connection conn = DBUtil.getConn();
  Statement state = null;
  ResultSet rs = null;
  Course course = null;

  try {
   state = conn.createStatement();
   rs = state.executeQuery(sql);
   while (rs.next()) {
    int id = rs.getInt("id");
    String place = rs.getString("place");
    String guige = rs.getString("guige");
    String number = rs.getString("number");
    course = new Course(id, name, place, guige,number);
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(rs, state, conn);
  }

  return course;
}

/**
* 查找
* @param name
* @param place
* @param guige
* @param number
* @return
*/
public List<Course> search(String name, String place, String guige,String number) {
  String sql = "select * from course where ";
  if (name != "") {
   sql += "name like '%" + name + "%'";
  }
  if (place != "") {
   sql += "place like '%" + place + "%'";
  }
  if (guige != "") {
   sql += "guige like '%" + guige + "%'";
  }
  if (number != "") {
   sql += "name like '%" + number + "%'";
  }
  List<Course> list = new ArrayList<>();
  Connection conn = DBUtil.getConn();
  Statement state = null;
  ResultSet rs = null;

  try {
   state = conn.createStatement();
   rs = state.executeQuery(sql);
   Course bean = null;
   while (rs.next()) {
    int id = rs.getInt("id");
    String name2 = rs.getString("name");
    String place2 = rs.getString("place");
    String guige2 = rs.getString("guige");
    String number2 = rs.getString("number2");
    bean = new Course(id, name2, place2, guige2,number2);
    list.add(bean);
   }
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(rs, state, conn);
  }

  return list;
}

/**
* 全部数据
* @param name
* @param place
* @param guige
* @return
*/
public List<Course> list() {
  String sql = "select * from course";
  List<Course> list = new ArrayList<>();
  Connection conn = DBUtil.getConn();
  Statement state = null;
  ResultSet rs = null;

}

增删改查方法的set层

package com.hjf.service;

import java.util.List;

import com.hjf.dao.CourseDao;
import com.hjf.entity.Course;

/**
* CourseService
* 服务层
* @author L
*
*/
public class CourseService {

CourseDao cDao = new CourseDao();

/**
* 添加
* @param course
* @return
*/
public boolean add(Course course) {
  boolean f = false;
  if(!cDao.name(course.getName())) {
   cDao.add(course);
   f = true;
  }
  return f;
}

/**
* 删除
*/
public void del(int id) {
  cDao.delete(id);
}

/**
* 修改
* @return
*/
public void update(Course course) {
  cDao.update(course);
}

/**
* 通过ID得到一个Course
* @return
*/
public Course getCourseById(int id) {
  return cDao.getCourseById(id);
}

/**
* 通过name得到一个Course
* @return
*/
public Course getCourseByName(String name) {
  return cDao.getCourseByName(name);
}

/**
* 查找
* @return
*/
public List<Course> search(String name, String place, String guige,String number) {
  return cDao.search(name, place, guige,number);
}

/**
* 全部数据
* @return
*/
public List<Course> list() {
  return cDao.list();
}
}

servelet层

package com.hjf.service;

import java.util.List;

import com.hjf.dao.CourseDao;
import com.hjf.entity.Course;

/**
* CourseService
* 服务层
* @author Hu
*
*/
public class CourseService {

连接数据库的DButil

package com.hjf.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

/**
* 数据库连接工具
* @author Hu
*
*/
public class DBUtil {

public static String db_url = "jdbc:mysql://localhost:3306/test?&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC";
public static String db_user = "root";
public static String db_pass = "root";

public static Connection getConn () {
  Connection conn = null;

  try {
   Class.forName("com.mysql.cj.jdbc.Driver");//连接数据库
   conn = DriverManager.getConnection(db_url, db_user, db_pass);
  } catch (Exception e) {
   e.printStackTrace();
  }

  return conn;
}

/**
* 关闭连接
* @param state
* @param conn
*/
public static void close (Statement state, Connection conn) {
  if (state != null) {
   try {
    state.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }

  if (conn != null) {
   try {
    conn.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }
}

public static void close (ResultSet rs, Statement state, Connection conn) {
  if (rs != null) {
   try {
    rs.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }

  if (state != null) {
   try {
    state.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }

  if (conn != null) {
   try {
    conn.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }
}

}

二、JSP

add.jsp

<%
      Object message = request.getAttribute("message");
      if(message!=null && !"".equals(message)){

%>
      <script type="text/javascript">
           alert("<%=request.getAttribute("message")%>");
      </script>
<%} %>
<div align="center">
  <h1 style="color: red;">物资信息录入</h1>
  <a href="index.jsp">返回主页</a>
  <form action="CourseServlet method=add" method="post" onsubmit="return check()">
   <div class="a">
    物资名称<input type="text" id="name" name="name"/>
   </div>
   <div class="a">
    生产厂家<input type="text" id="place" name="place" />
   </div>
   <div class="a">
    生产规格<input type="text" id="guige" name="guige" />
   </div>
   <div class="a">
    生产型号<input type="text" id="number" name="number" />
   </div>
   <div class="a">
    <button type="submit" class="b">保   存</button>
   </div>
  </form>
</div>
<script type="text/javascript">
  function check() {
   var name = document.getElementById("name");;
   var place = document.getElementById("place");
   var guige = document.getElementById("guige");
   var number = document.getElementById("number");

   //非空
   if(name.value == '')
   {
    alert('物资名称为空');
    name.focus();
    return false;
   }

   if(place.value == '')
   {
    alert('生产厂家为空');
    place.focus();
    return false;
   }

   if(guige.value == '')
   {
    alert('生产规格为空');
    guige.focus();
    return false;
   }

   if(number.value == '')
   {
    alert('生产型号为空');
    guige.focus();
    return false;
   }
}

</script>
</body>
</html>

del.jsp

detail.jsp （删除）

detail2.jsp （修改）

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style>
.a{
  margin-top: 20px;
}
.b{
  font-size: 20px;
  width: 160px;
  color: white;
  background-color: greenyellow;
}
</style>
</head>
<body>
<%
      Object message = request.getAttribute("message");
      if(message!=null && !"".equals(message)){

%>
      <script type="text/javascript">
           alert("<%=request.getAttribute("message")%>");
      </script>
<%} %>
<div align="center">
  <h1 style="color: red;">物资信息修改</h1>
  <a href="index.jsp">返回主页</a>
  <form action="CourseServlet?method=update" method="post" onsubmit="return check()">
   <div class="a">
    物资名称<input type="text" id="name" name="name" value="${course.name}"/>
   </div>
   <div class="a">
    生产厂家<input type="text" id="place" name="place" value="${course.place}"/>
   </div>
   <div class="a">
    生产规格<input type="text" id="guige" name="guige" value="${course.guige}"/>
   </div>
   <div class="a">
    生产型号<input type="text" id="number" name="number" value="${course.number}"/>
   </div>
   <input type="hidden" id="id" name="id" value="${course.id}"/>
   <div class="a">
    <button type="submit" class="b">修   改</button>
   </div>
  </form>
</div>
<script type="text/javascript">
  function check()
  {
   var name = document.getElementById("name");;
   var place = document.getElementById("place");
   var guige = document.getElementById("guige");
   var number = document.getElementById("number");

   //非空
   if(name.value == '')
   {
    alert('物资名称为空');
    name.focus();
    return false;
   }

   if(place.value == '')
   {
    alert('生产厂家为空');
    place.focus();
    return false;
   }

   if(guige.value == '')
   {
    alert('生产规格为空');
    guige.focus();
    return false;
   }

   if(number.value == '')
   {
    alert('生产型号为空');
    guige.focus();
    return false;
   }

  }
</script>
</body>
</html>

index.jsp（初始界面）

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>首页</title>
<style>
.a{
  font-size: 26px;
  margin-top: 20px;
}
</style>
</head>
<body>
<div align="center">
  <h1 style="color: red;">库存物资管理系统</h1>
  <div class="a">
   <a href="add.jsp">物资信息录入</a>
  </div>
  <div class="a">
   <a href="CourseServlet?method=list">物资信息修改</a>
  </div>
  <div class="a">
   <a href="del.jsp">物资信息删除</a>
  </div>
  <div class="a">
   <a href="search.jsp">物资信息查询</a>
  </div>
</div>
</body>
</html>

list.jsp（查询菜单）

search.jsp （搜索显示界面）

searchlist.jsp （遍历层）

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style>
.a{
  margin-top: 20px;
}
.b{
  font-size: 20px;
  width: 160px;
  color: white;
  background-color: greenyellow;
}
.tb, td {
  border: 1px solid black;
  font-size: 22px;
}
</style>
</head>
<body>
<div align="center">
  <h1 style="color: red;">物资信息列表</h1>
  <a href="index.jsp">返回主页</a>
  <table class="tb">
   <tr>
    <td>id</td>
    <td>物资名称</td>
    <td>生产厂家</td>
    <td>生产规格</td>
    <td>生产型号</td>
   </tr>
   
   <c:forEach items="${courses}" var="item" varStatus="status">
    <tr>
     <td>${item.id}</td>
     <td><a>${item.name}</a></td>
     <td>${item.place}</td>
     <td>${item.guige}</td>
     <td>${item.number}</td>
    </tr>
   </c:forEach>
  </table>
</div>
</body>
</html>

总结：革命尚未成功，同志仍需努力

来源：https://www.cnblogs.com/mitang0-0/p/10116843.html

标签

string

try

place