qhs200312 · qhs200312 · Jun 6, 2025
diff --git a/README.md b/README.md
@@ -1 +1,30 @@
-# javaee
+# Java EE Management System Skeleton
+
+This project provides a simple JSP/Servlet based management system.
+
+## Features
+
+- User registration with role selection (admin or user)
+- Login and session handling
+- Admin-only item management (add/delete)
+- Item listing for all users
+- Bootstrap-based interface
+
+## Project Structure
+
+```
+src/                  Java source files
+WebContent/jsp/       JSP pages
+WebContent/WEB-INF/   web.xml configuration
+schema.sql            MySQL schema
+```
+
+## Database Setup
+
+Import `schema.sql` into your MySQL server and adjust the credentials in
+`src/com/example/util/DBUtil.java`.
+
+## Build
+
+Use a servlet container such as Tomcat. Place the contents of this repository
+as a web application and compile the Java sources.
diff --git a/WebContent/WEB-INF/web.xml b/WebContent/WEB-INF/web.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<web-app xmlns="http://java.sun.com/xml/ns/javaee"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
+         version="3.0">
+    <welcome-file-list>
+        <welcome-file>jsp/index.jsp</welcome-file>
+    </welcome-file-list>
+</web-app>
diff --git a/WebContent/jsp/index.jsp b/WebContent/jsp/index.jsp
@@ -0,0 +1,4 @@
+<%@ page contentType="text/html;charset=UTF-8" %>
+<%
+response.sendRedirect("login.jsp");
+%>
diff --git a/WebContent/jsp/items.jsp b/WebContent/jsp/items.jsp
@@ -0,0 +1,77 @@
+<%@ page contentType="text/html;charset=UTF-8" %>
+<%@ page import="com.example.model.User" %>
+<%@ page import="java.util.List" %>
+<%@ page import="com.example.model.Item" %>
+<html>
+<head>
+    <title>Items</title>
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
+</head>
+<body class="container">
+<%
+User user = (User) session.getAttribute("user");
+if(user == null){
+    response.sendRedirect("login.jsp");
+    return;
+}
+%>
+<nav class="navbar navbar-expand-lg navbar-light bg-light mb-3">
+    <div class="container-fluid">
+        <a class="navbar-brand" href="#">Management</a>
+        <div class="collapse navbar-collapse">
+            <ul class="navbar-nav me-auto mb-2 mb-lg-0">
+                <li class="nav-item"><a class="nav-link" href="items">Items</a></li>
+                <li class="nav-item"><a class="nav-link" href="logout.jsp">Logout</a></li>
+            </ul>
+        </div>
+    </div>
+</nav>
+<h2>Items</h2>
+<%
+List<Item> list = (List<Item>) request.getAttribute("list");
+if(list == null){
+    list = new java.util.ArrayList<>();
+}
+String role = user.getRole();
+%>
+<% if("admin".equals(role)){ %>
+<form action="items" method="post" class="mb-3">
+    <input type="hidden" name="action" value="add">
+    <div class="row g-2">
+        <div class="col">
+            <input type="text" name="name" class="form-control" placeholder="Name" required>
+        </div>
+        <div class="col">
+            <input type="number" name="quantity" class="form-control" placeholder="Quantity" required>
+        </div>
+        <div class="col-auto">
+            <button type="submit" class="btn btn-primary">Add</button>
+        </div>
+    </div>
+</form>
+<% } %>
+<table class="table table-bordered">
+    <thead>
+        <tr><th>ID</th><th>Name</th><th>Quantity</th><% if("admin".equals(role)){ %><th>Actions</th><% } %></tr>
+    </thead>
+    <tbody>
+    <% for(Item item: list){ %>
+        <tr>
+            <td><%= item.getId() %></td>
+            <td><%= item.getName() %></td>
+            <td><%= item.getQuantity() %></td>
+            <% if("admin".equals(role)){ %>
+            <td>
+                <form action="items" method="post" style="display:inline">
+                    <input type="hidden" name="action" value="delete">
+                    <input type="hidden" name="id" value="<%= item.getId() %>">
+                    <button class="btn btn-danger btn-sm">Delete</button>
+                </form>
+            </td>
+            <% } %>
+        </tr>
+    <% } %>
+    </tbody>
+</table>
+</body>
+</html>
diff --git a/WebContent/jsp/login.jsp b/WebContent/jsp/login.jsp
@@ -0,0 +1,25 @@
+<%@ page contentType="text/html;charset=UTF-8" %>
+<html>
+<head>
+    <title>Login</title>
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
+</head>
+<body class="container">
+<h2>Login</h2>
+<% String error = request.getParameter("error"); if("1".equals(error)){ %>
+<div class="alert alert-danger">Invalid username or password</div>
+<% } %>
+<form action="login" method="post">
+    <div class="mb-3">
+        <label class="form-label">Username</label>
+        <input type="text" name="username" class="form-control" required>
+    </div>
+    <div class="mb-3">
+        <label class="form-label">Password</label>
+        <input type="password" name="password" class="form-control" required>
+    </div>
+    <button type="submit" class="btn btn-primary">Login</button>
+    <a href="register.jsp" class="btn btn-link">Register</a>
+</form>
+</body>
+</html>
diff --git a/WebContent/jsp/logout.jsp b/WebContent/jsp/logout.jsp
@@ -0,0 +1,5 @@
+<%@ page contentType="text/html;charset=UTF-8" %>
+<%
+session.invalidate();
+response.sendRedirect("login.jsp");
+%>
diff --git a/WebContent/jsp/register.jsp b/WebContent/jsp/register.jsp
@@ -0,0 +1,29 @@
+<%@ page contentType="text/html;charset=UTF-8" %>
+<html>
+<head>
+    <title>Register</title>
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
+</head>
+<body class="container">
+<h2>Register</h2>
+<form action="register" method="post">
+    <div class="mb-3">
+        <label class="form-label">Username</label>
+        <input type="text" name="username" class="form-control" required>
+    </div>
+    <div class="mb-3">
+        <label class="form-label">Password</label>
+        <input type="password" name="password" class="form-control" required>
+    </div>
+    <div class="mb-3">
+        <label class="form-label">Role</label>
+        <select name="role" class="form-select">
+            <option value="user">User</option>
+            <option value="admin">Admin</option>
+        </select>
+    </div>
+    <button type="submit" class="btn btn-primary">Register</button>
+    <a href="login.jsp" class="btn btn-link">Login</a>
+</form>
+</body>
+</html>
diff --git a/schema.sql b/schema.sql
@@ -0,0 +1,15 @@
+CREATE DATABASE IF NOT EXISTS management;
+USE management;
+
+CREATE TABLE IF NOT EXISTS users (
+    id INT PRIMARY KEY AUTO_INCREMENT,
+    username VARCHAR(50) UNIQUE NOT NULL,
+    password VARCHAR(100) NOT NULL,
+    role VARCHAR(10) NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS items (
+    id INT PRIMARY KEY AUTO_INCREMENT,
+    name VARCHAR(100) NOT NULL,
+    quantity INT NOT NULL
+);
diff --git a/src/com/example/dao/ItemDAO.java b/src/com/example/dao/ItemDAO.java
@@ -0,0 +1,80 @@
+package com.example.dao;
+
+import com.example.model.Item;
+import com.example.util.DBUtil;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ItemDAO {
+    public void insert(Item item) throws SQLException {
+        String sql = "INSERT INTO items(name,quantity) VALUES(?,?)";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)) {
+            ps.setString(1, item.getName());
+            ps.setInt(2, item.getQuantity());
+            ps.executeUpdate();
+            try (ResultSet rs = ps.getGeneratedKeys()) {
+                if (rs.next()) {
+                    item.setId(rs.getInt(1));
+                }
+            }
+        }
+    }
+
+    public void update(Item item) throws SQLException {
+        String sql = "UPDATE items SET name=?,quantity=? WHERE id=?";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql)) {
+            ps.setString(1, item.getName());
+            ps.setInt(2, item.getQuantity());
+            ps.setInt(3, item.getId());
+            ps.executeUpdate();
+        }
+    }
+
+    public void delete(int id) throws SQLException {
+        String sql = "DELETE FROM items WHERE id=?";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql)) {
+            ps.setInt(1, id);
+            ps.executeUpdate();
+        }
+    }
+
+    public Item findById(int id) throws SQLException {
+        String sql = "SELECT * FROM items WHERE id=?";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql)) {
+            ps.setInt(1, id);
+            try (ResultSet rs = ps.executeQuery()) {
+                if (rs.next()) {
+                    Item item = new Item();
+                    item.setId(rs.getInt("id"));
+                    item.setName(rs.getString("name"));
+                    item.setQuantity(rs.getInt("quantity"));
+                    return item;
+                }
+            }
+        }
+        return null;
+    }
+
+    public List<Item> listAll() throws SQLException {
+        List<Item> list = new ArrayList<>();
+        String sql = "SELECT * FROM items";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql);
+             ResultSet rs = ps.executeQuery()) {
+            while (rs.next()) {
+                Item item = new Item();
+                item.setId(rs.getInt("id"));
+                item.setName(rs.getString("name"));
+                item.setQuantity(rs.getInt("quantity"));
+                list.add(item);
+            }
+        }
+        return list;
+    }
+}
diff --git a/src/com/example/dao/UserDAO.java b/src/com/example/dao/UserDAO.java
@@ -0,0 +1,62 @@
+package com.example.dao;
+
+import com.example.model.User;
+import com.example.util.DBUtil;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class UserDAO {
+    public void insert(User user) throws SQLException {
+        String sql = "INSERT INTO users(username,password,role) VALUES(?,?,?)";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)) {
+            ps.setString(1, user.getUsername());
+            ps.setString(2, user.getPassword());
+            ps.setString(3, user.getRole());
+            ps.executeUpdate();
+            try (ResultSet rs = ps.getGeneratedKeys()) {
+                if (rs.next()) {
+                    user.setId(rs.getInt(1));
+                }
+            }
+        }
+    }
+
+    public User findByUsername(String username) throws SQLException {
+        String sql = "SELECT * FROM users WHERE username=?";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql)) {
+            ps.setString(1, username);
+            try (ResultSet rs = ps.executeQuery()) {
+                if (rs.next()) {
+                    User user = new User();
+                    user.setId(rs.getInt("id"));
+                    user.setUsername(rs.getString("username"));
+                    user.setPassword(rs.getString("password"));
+                    user.setRole(rs.getString("role"));
+                    return user;
+                }
+            }
+        }
+        return null;
+    }
+
+    public List<User> listAll() throws SQLException {
+        List<User> list = new ArrayList<>();
+        String sql = "SELECT * FROM users";
+        try (Connection conn = DBUtil.getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql);
+             ResultSet rs = ps.executeQuery()) {
+            while (rs.next()) {
+                User user = new User();
+                user.setId(rs.getInt("id"));
+                user.setUsername(rs.getString("username"));
+                user.setRole(rs.getString("role"));
+                list.add(user);
+            }
+        }
+        return list;
+    }
+}
diff --git a/src/com/example/model/Item.java b/src/com/example/model/Item.java
@@ -0,0 +1,16 @@
+package com.example.model;
+
+public class Item {
+    private int id;
+    private String name;
+    private int quantity;
+
+    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 int getQuantity() { return quantity; }
+    public void setQuantity(int quantity) { this.quantity = quantity; }
+}
diff --git a/src/com/example/model/User.java b/src/com/example/model/User.java
@@ -0,0 +1,20 @@
+package com.example.model;
+
+public class User {
+    private int id;
+    private String username;
+    private String password;
+    private String role; // admin or user
+
+    public int getId() { return id; }
+    public void setId(int id) { this.id = id; }
+
+    public String getUsername() { return username; }
+    public void setUsername(String username) { this.username = username; }
+
+    public String getPassword() { return password; }
+    public void setPassword(String password) { this.password = password; }
+
+    public String getRole() { return role; }
+    public void setRole(String role) { this.role = role; }
+}