前面咱們作的小項目都是一個表的,業務代碼也相對簡單。如今咱們來作一個權限管理系統,體驗一下多表的業務邏輯,順便鞏固一下過濾器的知識!javascript
如今我有一個管理商品、訂單的頁面。當用戶點擊某個超連接時,過濾器會檢測該用戶是否有權限!php
按照面向對象的思想,咱們至少應該有權限(Privilege)和用戶(User)實體。兩個實體足夠了嗎?細想一下,若是咱們有多個用戶,多個用戶也有多個權限,當要爲用戶受權的時候,這樣子就會很是麻煩!因此咱們應該引入角色(Role)這個實體!html
引入角色(Role)這個實體方便在哪呢??把權限賦給角色(好比:把刪除、修改的權限給管理員這個角色),管理員這個角色再賦給用戶,那麼該用戶就有了修改、刪除的權限了!java
權限和角色是多對多的關係,角色和用戶也是多對多的關係!web
public class User { private String id; private String username; private String password; //記住角色 private Set<Role> roles = new HashSet<>(); //各類getter和setter..... }
public class Role { private String id; private String name; private String description; //記住全部的用戶 private Set<User> users = new HashSet<>(); //記住全部的權限 private Set<Privilege> privileges = new HashSet<>(); //各類getter和setter..... }
public class Privilege { private String id; private String name; private String description; //記住全部的角色 private Set<Role> roles = new HashSet<>(); //各類getter和setter..... }
用戶和角色、角色和權限都是多對多的關係,這是毋庸置疑的!咱們也按照面向對象的方法來設計,用集合來記住另外一方的數據!sql
可是呢,咱們想一想:數據庫
答案是沒有的,通常咱們都不會顯示出來。因此,權限的實體不必使用Set集合來記住角色,角色實體不必使用Set集合來記住用戶!後端
public class Privilege { private String id; private String name; private String description; //各類setter和getter方法 }
public class Role { private String id; private String name; private String description; //記住全部的權限 private Set<Privilege> privileges = new HashSet<>(); //各類setter和getter方法 }
CREATE TABLE user ( id VARCHAR(20) PRIMARY KEY, username VARCHAR(20) NOT NULL, password VARCHAR(20) NOT NULL );
CREATE TABLE role ( id VARCHAR(20) PRIMARY KEY, name VARCHAR(20) NOT NULL, description VARCHAR(255) );
CREATE TABLE privilege ( id VARCHAR(20) PRIMARY KEY, name VARCHAR(20) NOT NULL, description VARCHAR(255) );
CREATE TABLE user_role ( user_id VARCHAR(20), role_id VARCHAR(20), PRIMARY KEY (user_id, role_id), CONSTRAINT user_id_FK FOREIGN KEY (user_id) REFERENCES user (id), CONSTRAINT role_id_FK FOREIGN KEY (role_id) REFERENCES role (id) );
CREATE TABLE role_privilege ( role_id VARCHAR(20), privilege_id VARCHAR(20), PRIMARY KEY (role_id, privilege_id), CONSTRAINT role_id_FK1 FOREIGN KEY (role_id) REFERENCES role (id), CONSTRAINT privilege_id_FK FOREIGN KEY (privilege_id) REFERENCES privilege (id) );
注意:user和role的關係表、role和privilege的關係都有role_id做爲外鍵,外鍵的名稱是不能同樣的!瀏覽器
/** * 權限的管理應該有如下的功能: * 1.添加權限 * 2.查看全部權限 * 3.查找某個權限 * * */ public class PrivilegeDao { /*添加權限*/ public void addPrivilege(Privilege privilege) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "INSERT INTO privilege (id, name, description) VALUE (?, ?, ?)"; queryRunner.update(sql, new Object[]{privilege.getId(), privilege.getName(), privilege.getDescription()}); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加權限失敗了!"); } } /*查找權限*/ public Privilege findPrivilege(String id) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT *FROM privilege WHERE id = ?"; Privilege privilege = (Privilege) queryRunner.query(sql, new BeanHandler(Privilege.class), new Object[]{id}); return privilege; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("查找權限失敗了!"); } } /*獲取全部的權限*/ public List<Privilege> getAllPrivileges() { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT * FROM privilege "; List<Privilege> privileges = (List<Privilege>) queryRunner.query(sql, new BeanListHandler(Privilege.class)); return privileges; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("查找權限失敗了!"); } } }
爲了測試方便,添加有參構造函數到Privilege對象中服務器
public class PrivilegeDaoTest { PrivilegeDao privilegeDao = new PrivilegeDao(); @Test public void add() { Privilege privilege = new Privilege("2", "修改", "修改功能"); privilegeDao.addPrivilege(privilege); } @Test public void getAll() { List<Privilege> list = privilegeDao.getAllPrivileges(); for (Privilege privilege : list) { System.out.println(privilege.getId()); } } @Test public void find() { String id = "2"; Privilege privilege = privilegeDao.findPrivilege(id); System.out.println(privilege.getName()); } }
public class UserDao { public void addUser(User user) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "INSERT INTO user (id,username,password) VALUES(?,?,?)"; queryRunner.update(sql, new Object[]{user.getId(), user.getUsername(), user.getPassword()}); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加權限失敗了!"); } } public User find(String id) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT * FROM user WHERE id=?"; User user = (User) queryRunner.query(sql, new BeanHandler(User.class), new Object[]{id}); return user; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加權限失敗了!"); } } public List<User> getAll() { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT * FORM user"; List<User> users = (List<User>) queryRunner.query(sql, new BeanListHandler(User.class)); return users; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加權限失敗了!"); } } }
public class UserDaoTest { UserDao userDao = new UserDao(); @Test public void add() { User user = new User(); user.setId("2"); user.setUsername("qqq"); user.setPassword("123"); userDao.addUser(user); } @Test public void find() { String id = "1"; User user = userDao.find(id); System.out.println(user.getUsername()); } @Test public void findALL() { List<User> userList = userDao.getAll(); for (User user : userList) { System.out.println(user.getUsername()); } } }
public void add(Role role){ try{ QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "insert into role(id,name,description) values(?,?,?)"; Object params[] = {role.getId(),role.getName(),role.getDescription()}; runner.update(sql, params); }catch (Exception e) { throw new RuntimeException(e); } } public Role find(String id){ try{ QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "select * from role where id=?"; return (Role) runner.query(sql, id, new BeanHandler(Role.class)); }catch (Exception e) { throw new RuntimeException(e); } } //獲得全部角色 public List<Role> getAll(){ try{ QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "select * from role"; return (List<Role>) runner.query(sql, new BeanListHandler(Role.class)); }catch (Exception e) { throw new RuntimeException(e); } }
RoleDao roleDao = new RoleDao(); @Test public void add() { Role role = new Role(); role.setId("1"); role.setName("manager"); role.setDescription("this is a manager"); roleDao.add(role); } @Test public void find( ) { String id = "1"; Role role = roleDao.find(id); System.out.println(role.getName()); } @Test public void getAdd() { List<Role> roleList = roleDao.getAll(); for (Role role : roleList) { System.out.println(role.getName()); } }
上面的僅僅是單表的Dao功能,User和Role表是多對多的關係,Role和Privilege表也是多對多的關係。
前面已經分析了
因此應該在UserDao有獲取某用戶全部的角色的方法:
/*獲得用戶的全部角色*/ public List<Role> getRoles(String user_id) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); //根據用戶id查詢全部角色,重點就在角色上,因此要有role表。而後查詢user_role表,就能夠鎖定用戶id對應的角色了! String sql = "SELECT r.* FROM role r, user_role ur WHERE ur.user_id = ? AND r.id = ur.role_id "; List<Role> roles = (List<Role>) queryRunner.query(sql, new BeanListHandler(Role.class), new Object[]{user_id}); return roles; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("獲得用戶全部的角色失敗了!"); } }
在RoleDao有獲取全部權限的方法:
//獲得某角色的全部權限【權限表、權限和角色關系表】 public List<Privilege> getPrivileges(String role_id) { try{ QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT p.* FROM privilege p, role_privilege rp WHERE rp.role_id = ? AND p.id = rp.role_id"; List<Privilege> privileges = (List<Privilege>) runner.query(sql, new BeanListHandler(Privilege.class), new Object[]{role_id}); return privileges; }catch (Exception e) { throw new RuntimeException(e); } }
咱們既然能獲取獲得用戶全部的角色了,獲取獲得角色全部的權限了。那天然咱們就應該有修改用戶的角色功能,修改角色的權限的功能啦!
咱們先來分析一下它怎麼寫:要修改用戶所擁有的角色,應該知道修改用戶是哪個,因此須要用戶的id或者User對象!修改的角色是什麼,須要Role對象或者裝載Role對象的集合!
在UserDao有修改某用戶角色的方法,咱們是想把全部的角色都刪除了,再添加新的角色
//更新用戶的角色 public void updateRole(User user, List<Role> roles) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); //先把用戶原來的全部角色刪掉了 String delete = "DELETE FROM user_role WHERE user_id = ?"; queryRunner.update(delete, user.getId()); String add = "INSERT INTO user_role (user_id,role_id) VALUES(?,?)"; for (Role role : roles) { queryRunner.update(add, new Object[]{user.getId(), role.getId()}); } } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加權限失敗了!"); } }
在RoleDao有修改角色權限的方法,和上面是相似的。
//爲某個角色受權 public void addPrivilege2Role(Role role, List<Privilege> privileges) { try{ QueryRunner runner = new QueryRunner(JdbcUtils.getDataSource()); //先刪除該角色的全部權限 String delete = "DELETE FROM role_privilege WHERE role_id = ?"; runner.update(delete, new Object[]{role.getId()}); //賦予角色新的權限 String sql = "INSERT INTO role_privilege (role_id, privilege_id) VALUES (?, ?)"; for (Privilege privilege : privileges) { runner.update(sql, new Object[]{role.getId(), privilege.getId()}); } }catch (Exception e) { throw new RuntimeException(e); } }
public class UserService { UserDao userDao = new UserDao(); //添加用戶 public void addUser(User user) { userDao.addUser(user); } //根據id查找用戶 public User findUser(String id) { return userDao.find(id); } //獲得全部的用戶 public List<User> getAllUser() { return userDao.getAll(); } //獲取用戶全部的角色 public List<Role> getUserRole(String user_id) { return userDao.getRoles(user_id); } //修改用戶的角色 public void updateUserRole(User user, List<Role> roles) { userDao.updateRole(user, roles); } }
public class RoleService { RoleDao roleDao = new RoleDao(); //添加角色 public void addRole(Role role) { roleDao.add(role); } //根據id查找角色 public Role findRole(String id) { return roleDao.find(id); } //獲取全部的角色 public List<Role> getAllRole() { return roleDao.getAll(); } //獲取角色全部的權限 public List<Privilege> getRolePrivilege(String role_id) { return roleDao.getPrivileges(role_id); } //修改角色的權限 public void updateRolePrivilege(Role role, List<Privilege> privileges) { roleDao.addPrivilege2Role(role, privileges); } }
public class PrivilegeService { PrivilegeDao privilegeDao = new PrivilegeDao(); //添加權限 public void addPrivilege(Privilege privilege) { privilegeDao.addPrivilege(privilege); } //根據id得到權限 public Privilege findPrivilege(String id) { return privilegeDao.findPrivilege(id); } //獲取全部的權限 public List<Privilege> getAllPrivileges() { return privilegeDao.getAllPrivileges(); } }
//直接跳轉到顯示添加用戶的界面 request.getRequestDispatcher("/WEB-INF/jsp/addUser.jsp").forward(request, response);
<form action="AddUserController" method="post"> <table> <tr> <td>用戶名:</td> <td><input type="text" name="username"></td> </tr> <tr> <td>密碼:</td> <td><input type="password" name="password"></td> </tr> <tr> <td><input type="submit" value="添加用戶"></td> <td><input type="reset" value="重置"></td> </tr> </table> </form>
//獲得客戶端傳遞進來的參數 String username = request.getParameter("username"); String password = request.getParameter("password"); User user = new User(); user.setId(WebUtils.makeId()); user.setUsername(username); user.setPassword(password); try { UserService userService = new UserService(); userService.addUser(user); request.setAttribute("message","添加用戶成功!"); } catch (Exception e) { request.setAttribute("message", "添加用戶失敗!"); throw new RuntimeException("在Controller添加客戶失敗"); } request.getRequestDispatcher("/message.jsp").forward(request,response); }
UserService userService = new UserService(); List<User> list = userService.getAllUser(); request.setAttribute("list", list); //跳轉到顯示頁面 request.getRequestDispatcher("/WEB-INF/jsp/LookUser.jsp").forward(request, response);
<c:if test="${empty(list)}"> 對不起,暫時沒有任何客戶 </c:if> <c:if test="${!empty(list)}"> <table border="1px"> <tr> <td>用戶名</td> <td>密碼</td> </tr> <c:forEach items="${list}" var="user"> <tr> <td>${user.username}</td> <td>${user.password}</td> </tr> </c:forEach> </table> </c:if>
在顯示用戶的基礎上,應該添加爲用戶受權角色的超連接。
<table border="1px"> <tr> <td>用戶名</td> <td>密碼</td> <td>操做</td> </tr> <c:forEach items="${list}" var="user"> <tr> <td>${user.username}</td> <td>${user.password}</td> <td> <a href="${pageContext.request.contextPath}/LookUserRole?user_id=${user.id}"> 爲用戶受權角色 </a> <a href="#">修改用戶</a> <a href="#">刪除用戶</a> </td> </tr> </c:forEach> </table>
//獲得客戶端傳遞過來的user_id String user_id = request.getParameter("user_id"); //獲取該用戶全部的角色 UserService userService = new UserService(); List<Role> userRoles = userService.getUserRole(user_id); //獲得所有的角色 RoleService roleService = new RoleService(); List<Role> allRoles = roleService.getAllRole(); //爲用戶受權的JSP頁面也應該顯示用戶的信息,因此把User對象也傳遞過去給JSP頁面 User user = userService.findUser(user_id); request.setAttribute("user", user); request.setAttribute("userRoles", userRoles); request.setAttribute("allRoles", allRoles); //跳轉到顯示頁面 request.getRequestDispatcher("/WEB-INF/jsp/LookUserRole.jsp").forward(request, response);
<table border="1px"> <tr> <td>當前用戶名稱</td> <td>${user.username}</td> </tr> <tr> <td>當前用戶所擁有的角色</td> <td> <c:forEach items="${userRoles}" var="userRole"> ${userRole.name} </c:forEach> </td> </tr> <tr> <td>當前系統所擁有的角色</td> <td> <form method="post" action="${pageContext.request.contextPath}/AddUserRole"> <%--要爲用戶添加角色,須要知道是哪個用戶,經過hidden傳遞過去用戶的id--%> <input type="hidden" name="user_id" value="${user.id}"> <c:forEach items="${allRoles}" var="roles"> <input type="checkbox" name="role_id" value="${roles.id}">${roles.name} </c:forEach> <input type="submit" value="添加角色!"> </form> </td> </tr> </table>
//獲得傳遞進來的role_id String[] ids = request.getParameterValues("role_id"); try { //獲得想要修改哪一個用戶的id String user_id = request.getParameter("user_id"); //經過id獲取獲得User對象 UserService userService = new UserService(); User user = userService.findUser(user_id); //經過id獲取獲得Role對象,再把對象用List集合裝載起來 RoleService roleService = new RoleService(); List<Role> list = new ArrayList<>(); for (String id : ids) { Role role = roleService.findRole(id); list.add(role); } //更新用戶所擁有的角色 userService.updateUserRole(user, list); request.setAttribute("message","添加角色成功!"); } catch (Exception e) { e.printStackTrace(); request.setAttribute("message","添加角色失敗!"); } request.getRequestDispatcher("/message.jsp").forward(request,response);
//直接跳轉到jsp頁面便可 request.getRequestDispatcher("WEB-INF/jsp/AddRole.jsp").forward(request, response);
<form action="${pageContext.request.contextPath}/AddRoleController" method="post"> <table border="1px"> <tr> <td>角色名稱</td> <td><input type="text" name="name"></td> </tr> <tr> <td>詳細描述</td> <td><textarea name="description" cols="30" rows="10"></textarea></td> </tr> <tr> <td> <input type="submit" value="添加角色"> </td> </tr> </table> </form>
//獲得客戶端帶過來的數據 String name = request.getParameter("name"); String description = request.getParameter("description"); try { //建立對象並封裝數據 Role role = new Role(); role.setId(WebUtils.makeId()); role.setName(name); role.setDescription(description); //調用Service方法,完成功能 RoleService roleService = new RoleService(); roleService.addRole(role); request.setAttribute("message","添加角色成功!"); } catch (Exception e) { request.setAttribute("message","添加角色失敗!"); e.printStackTrace(); } request.getRequestDispatcher("/message.jsp").forward(request, response);
//獲得全部的角色 RoleService roleService = new RoleService(); List<Role> list = roleService.getAllRole(); request.setAttribute("list", list); request.getRequestDispatcher("/WEB-INF/jsp/LookRoles.jsp").forward(request, response);
<c:if test="${empty(list)}"> 您尚未任何角色,請添加! </c:if> <c:if test="${!empty(list)}"> <table border="1px"> <tr> <td>角色名稱</td> <td>描述</td> </tr> <c:forEach items="${list}" var="role"> <tr> <td>${role.name}</td> <td>${role.description}</td> </tr> </c:forEach> </table> </c:if>
與上面是相似的,咱們要在查看角色的時候,添加受權的功能!
<c:forEach items="${list}" var="role"> <tr> <td>${role.name}</td> <td>${role.description}</td> <td> <a href="${pageContext.request.contextPath}/LookRolePrivilege?role_id=${role.id}"> 爲角色受權 </a> <a href="#">刪除角色</a> <a href="#">修改角色</a> </td> </tr> </c:forEach>
//獲得瀏覽器想要查看的角色id String role_id = request.getParameter("role_id"); RoleService roleService = new RoleService(); //根據id獲取獲得Role對象 Role role = roleService.findRole(role_id); //獲得當前角色全部的權利 List<Privilege> rolePrivilege = roleService.getRolePrivilege(role_id); //獲得系統全部的權利 PrivilegeService privilegeService = new PrivilegeService(); List<Privilege> allPrivilege = privilegeService.getAllPrivileges(); request.setAttribute("role", role); request.setAttribute("rolePrivilege", rolePrivilege); request.setAttribute("allPrivilege", allPrivilege); //跳轉到顯示頁面 request.getRequestDispatcher("/WEB-INF/jsp/LookRolePrivilege.jsp").forward(request, response);
<table border="1px"> <tr> <td>角色名稱</td> <td>${role.name}</td> </tr> <tr> <td>當前角色擁有的權利</td> <td> <c:forEach items="${rolePrivilege}" var="privi"> ${privi.name} </c:forEach> </td> </tr> <tr> <td>系統擁有的全部權利</td> <td> <form action="${pageContext.request.contextPath}/AddRolePrivilegeController" method="post"> <%--讓服務器知道要修改哪個用戶,就要把用戶的id傳遞過去--%> <input type="hidden" name="role_id" value="${role.id}"> <c:forEach items="${allPrivilege}" var="privileges"> <input type="checkbox" name="privilege" value="${privileges.id}">${privileges.name} </c:forEach> <input type="submit" value="添加權利"> </form> </td> </tr> </table>
//獲得瀏覽器想要添加權利的id String[] ids = request.getParameterValues("privilege_id"); //獲取角色id String role_id = request.getParameter("role_id"); try { //獲得想要添加權利的角色 RoleService roleService = new RoleService(); Role role = roleService.findRole(role_id); //獲得權利對象,用List對象裝載起來 PrivilegeService privilegeService = new PrivilegeService(); List<Privilege> privileges_list = new ArrayList<>(); for (String id : ids) { Privilege privilege = privilegeService.findPrivilege(id); privileges_list.add(privilege); } roleService.updateRolePrivilege(role, privileges_list); request.setAttribute("message","爲角色添加權利成功!"); } catch (Exception e) { e.printStackTrace(); request.setAttribute("message","爲角色添加權利失敗!"); } request.getRequestDispatcher("/message.jsp").forward(request, response);
//直接跳轉到jsp頁面 request.getRequestDispatcher("/WEB-INF/jsp/AddPrivilege.jsp").forward(request, response);
<form action="${pageContext.request.contextPath}/AddPrivilegeController" method="post"> <table border="1px"> <tr> <td>權限名字</td> <td><input type="text" name="name"></td> </tr> <tr> <td>權限描述</td> <td><textarea name="description" cols="30" rows="10"></textarea></td> </tr> <tr> <td><input type="submit" value="添加權限"></td> <td><input type="reset" value="重置"></td> </tr> </table> </form>
//獲得瀏覽器帶過來的數據 String name = request.getParameter("name"); String description = request.getParameter("description"); //封裝數據到Privilege對象 Privilege privilege = new Privilege(); privilege.setId(WebUtils.makeId().substring(3,10)); privilege.setName(name); privilege.setDescription(name); try { PrivilegeService privilegeService = new PrivilegeService(); privilegeService.addPrivilege(privilege); request.setAttribute("message","添加權限成功!"); } catch (Exception e) { e.printStackTrace(); request.setAttribute("message", "添加權限失敗!"); } request.getRequestDispatcher("/message.jsp").forward(request, response);
//獲得全部的權限 PrivilegeService privilegeService = new PrivilegeService(); List<Privilege> list = privilegeService.getAllPrivileges(); request.setAttribute("list", list); request.getRequestDispatcher("/WEB-INF/jsp/LookPrivileges.jsp").forward(request, response);
<c:if test="${empty(list)}"> 您還沒添加任何的權限 </c:if> <c:if test="${!empty(list)}"> <table border="1px"> <tr> <td>權限名稱</td> <td>描述</td> <td>操做</td> </tr> <c:forEach items="${list}" var="privilege"> <tr> <td>${privilege.name}</td> <td>${privilege.description}</td> <td> <a href="#">刪除權限</a> <a href="#">修改權限</a> </td> </tr> </c:forEach> </table> </c:if>
<body style="text-align: center"> <h1>XX管理系統</h1> </body>
<body> <a href="${pageContext.request.contextPath}/LookUserUI" target="body">用戶管理</a><br><br><br><br> <a href="${pageContext.request.contextPath}/LookRolesUI" target="body">角色管理</a><br><br><br><br> <a href="${pageContext.request.contextPath}/LookPrivileges" target="body">權限管理</a><br><br><br><br> </body>
body頁面是空白的!
index頁面:
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>$Title$</title> </head> <frameset rows="25%,*"> <frame src="head.jsp" name="head"> <frameset cols="15%,*"> <frame src="left.jsp" name="left"> <frame src="body.jsp" name="body"> </frameset> </frameset> </html>
過濾器主要的工做就是:點擊超連接時,過濾器會檢測該點擊者是否有權限進入頁面進行操做(CURD)。
這裏咱們是這樣子作的:uri做爲key,權限做爲value,構成一個Map集合。當用戶請求資源的時候,判斷該資源是否須要權限,若是須要權限,就判斷該用戶是否登錄了,若是登錄了,就判斷該用戶有沒有權限去訪問該資源!
public User login(String username, String password) { try { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT * FROM user WHERE username=? AND password=?"; User user = (User) queryRunner.query(sql, new BeanHandler(User.class), new Object[]{username, password}); return user; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("登錄失敗了!!"); } }
<form action="${pageContext.request.contextPath}/LoginController" method="post"> 用戶名:<input type="text" name="username"><br> 密碼:<input type="password" name="password"><br> <input type="submit" value="登錄"><br> </form>
//獲取表單數據 String username = request.getParameter("username"); String password = request.getParameter("password"); UserService userService = new UserService(); User user = userService.login(username, password); if (user != null) { request.setAttribute("message", "恭喜你,登錄成功了!"); request.getSession().setAttribute("user", user); } else { request.setAttribute("message","用戶名或密碼出錯了!!"); } request.getRequestDispatcher("/message.jsp").forward(request, response);
private Map<String, Privilege> map = new HashMap<>(); public void init(FilterConfig config) throws ServletException { map.put("/addServlet", new Privilege("增長")); map.put("/deleteServlet", new Privilege("刪除")); map.put("/updateServlet", new Privilege("修改")); map.put("/findServlet", new Privilege("查帳單")); } public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException { HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) resp; //獲得用戶請求的資源地址 String uri = request.getRequestURI(); System.out.println(uri); //經過key獲取值,看看能不能獲取獲得值【爲空,就是不須要權限了】 if (map.get(uri) == null) { chain.doFilter(request, response); System.out.println("放行了"); return ; } //若是不爲空,就是須要權限。須要權限的話,就判斷請求者是否登錄了! if (request.getSession().getAttribute("user") == null) { request.setAttribute("message", "您登錄了再來操做把!"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; } //若是登錄了,就查一下用戶的權限是否和訪問資源的權限匹配 User user = (User) request.getSession().getAttribute("user"); UserService userService = new UserService(); RoleService roleService = new RoleService(); //獲得用戶全部的角色 List<Role> roles = userService.getUserRole(user.getId()); //經過角色,獲得全部的權限【一個角色有多個權限,若是用戶角色不少,那麼權限也就不少了】 //此時,咱們又要用集合來裝載每個角色的權限了! Set privileges = new HashSet(); for (Role role : roles) { List<Privilege> list = roleService.getRolePrivilege(role.getId()); privileges.addAll(list); } //獲得的Set集合就是用戶全部的權限了!!!!! //集合的contains方法比較的是默認對象,而咱們想要比較的是字符串名稱,因此咱們要在Privilege對象中重寫equals和hashCode方法! if (!privileges.contains(map.get(uri))) { request.setAttribute("message", "你沒有權限喲"); request.getRequestDispatcher("/message.jsp").forward(request, response); return ; } //到這裏,就是有權限了 chain.doFilter(request, response); } public void destroy() { }
①:用戶和權限的關係,因爲添加用戶的權限和修改用戶權限的不足,因此咱們引入了角色這個概念
②:用戶與角色,角色與權限都是多對多的關係
③:按照數據庫範式,咱們會建立5張實體表,其中兩張是表明着:用戶與角色、角色與權限的關係表。角色這個字段在外鍵中,不能同名!
④:不管是角色、用戶、權限都有這三個方法:獲得全部的權限(角色、用戶)、添加權限(角色、用戶)、權限的id獲得權限(角色、用戶)對象
⑤:根據id獲得具體的對象方法的意義:在web顯示層只能經過id來標識着這個對象,然而在後端經常使用的是對象,因而就有了這個方法。
⑥:多對多之間的關係,在程序中並非都要在其類上定義一個集合來記住對方。當顯示用戶時,須要顯示角色,可是顯示角色時,通常咱們是不須要顯示用戶的信息的。所以在角色上,並不須要維護一個集合來記住全部的用戶
⑦:獲得用戶的全部角色:傳入的參數一定有具體的用戶或角色,因此id必須是外界傳遞進來的。【獲得角色的全部權限是同理】
⑧:修改用戶的角色:咱們先把用戶的角色所有刪除了,再經過外界勾選的角色進行添加【修改角色的權限是同理】
⑨:在添加用戶角色的時候,要把用戶的id經過隱藏域傳遞進去給服務器端,否則是不知道要修改的是哪個用戶的角色的。【修改角色的權限是同理】
⑩:frameset和frame來實現前臺的分幀,target指定在哪裏顯示具體的數據
①①:在init()方法中用一個Map集合,以uri做爲key,以具體的權限做爲值來實現過濾
①②:若是uri不須要權限,直接放行。須要權限,那麼判斷該用戶是否登陸了。沒有登陸就讓用戶去登陸
①③:若是登陸了,就獲得用戶全部的權限,權限用一個Set集合裝載,遍歷Set集合,使用contains()方法就能夠查看出有沒有對應的權限了。
①④:使用contains()方法須要在權限類上重寫hashCode()和equals()方法的。由於咱們比較的是字符串。