【愚公系列】2023年05月 Java面面刷题系统-004.登录和权限校验

一、登录和权限校验

1. 登陆

1.1 登陆功能快速开发

1、找到项目webapp/login.jsp登陆页面，修改form表单提交的action路径

<form action="${pageContext.request.contextPath}/login?operation=login" method="post">
</form>

2、在后台UserServlet添加登陆的方法

@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String operation = request.getParameter("operation");
if("list".equals(operation)){
this.list(request,response);
}
//中间省略
else if("login".equals(operation)){
this.login(request,response);
}
}
private void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String email = request.getParameter("email");
String pwd = request.getParameter("password");
User user = userService.login(email,pwd);
if(user != null) {
request.getSession().setAttribute("loginUser", user);
//跳转页面
request.getRequestDispatcher("/WEB-INF/pages/home/main.jsp").forward(request, response);
}else{
response.sendRedirect(request.getContextPath()+"/login.jsp");
}
}

3、在因为层接口UserService中添加登陆的方法

/**
* 根据邮箱和密码登录
* @param email
* @param pwd
* @return
*/
User login(String email, String pwd);

4、在对应的实现类中去实现登陆方法

@Override
public User login(String email, String pwd) {
SqlSession sqlSession = null;
try{
//1.获取SqlSession
sqlSession = MapperFactory.getSqlSession();
//2.获取Dao
UserDao userDao = MapperFactory.getMapper(sqlSession,UserDao.class);
//3.调用Dao层操作
pwd = MD5Util.md5(pwd);
return userDao.findByEmailAndPwd(email,pwd);
}catch (Exception e){
throw new RuntimeException(e);
//记录日志
}finally {
try {
TransactionUtil.close(sqlSession);
}catch (Exception e){
e.printStackTrace();
}
}
}

5、在UserDao接口中添加查询方法

User findByEmailAndPwd(@Param("email")String email, @Param("password")String pwd);

6、在UserDao.xml中添加查询

<select id="findByEmailAndPwd" parameterType="map" resultMap="BaseResultMap">
select
<include refid="Base_Column_List"/>
from ss_user
where email = #{email,jdbcType=VARCHAR} and password = #{password,jdbcType=VARCHAR}
</select>

7、修改/WEB-INF/pages/home/main.jsp内容区的路径

<!-- 内容区域 -->
<div class="content-wrapper">
<iframe id="iframe" name="iframe"
style="overflow:visible;"
scrolling="auto"
frameborder="no" height="100%" width="100%"
src="${ctx}/system/user?operation=home"></iframe>
</div>

8、在后台UserServlet中添加方法

@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String operation = request.getParameter("operation");
if("list".equals(operation)){
this.list(request,response);
}
//中间省略
else if("home".equals(operation)){
this.home(request,response);
}
}
private void home(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.getRequestDispatcher("/WEB-INF/pages/home/home.jsp").forward(request, response);
}

1.2 用户菜单控制数据准备

我们先来完成登陆后的注销操作，这是一套的

1、找到/WEB-INF/pages/home/header.jsp中找到注销，添加请求连接

<div class="pull-right">
<a href="${ctx}/system/user?operation=logout" class="btn btn-default btn-flat">注销</a>
</div>

2、在后台UserServlet中添加对应的方法logout

@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String operation = request.getParameter("operation");
if("list".equals(operation)){
this.list(request,response);
}
//中间的省略
else if("login".equals(operation)){
this.login(request,response);
}else if("logout".equals(operation)){
this.logout(request,response);
}else if("home".equals(operation)){
this.home(request,response);
}
}
private void logout(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.getSession().removeAttribute("loginUser");
response.sendRedirect(request.getContextPath()+"/login.jsp");
}

3、在用户登陆的时候需要去查询该用户对应的角色对应的所有模块，因此需要在后台的UserServlet中修改用户登陆的方法，添加数据的查询

private void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String email = request.getParameter("email");
String pwd = request.getParameter("password");
User user = userService.login(email,pwd);
if(user != null) {
request.getSession().setAttribute("loginUser", user);
//如果登录成功，加载该用户对应的角色对应的所有模块
List<Module> moduleList = userService.findModuleById(user.getId());
request.setAttribute("moduleList",moduleList);
//跳转页面
request.getRequestDispatcher("/WEB-INF/pages/home/main.jsp").forward(request, response);
}else{
response.sendRedirect(request.getContextPath()+"/login.jsp");
}
}

4、在UserService接口中添加方法findModuleById

/**
* 根据用户id查询所有可以操作的菜单对象
* @param id 用户的id
* @return
*/
List<Module> findModuleById(String id);

5、在实现类中去实现该方法

@Override
public List<Module> findModuleById(String id) {
SqlSession sqlSession = null;
try{
//1.获取SqlSession
sqlSession = MapperFactory.getSqlSession();
//2.获取Dao
ModuleDao moduleDao = MapperFactory.getMapper(sqlSession,ModuleDao.class);
//3.调用Dao层操作
return moduleDao.findModuleByUserId(id);
}catch (Exception e){
throw new RuntimeException(e);
//记录日志
}finally {
try {
TransactionUtil.close(sqlSession);
}catch (Exception e){
e.printStackTrace();
}
}
}

6、在ModuleDao接口中添加查询方法findModuleByUserId

List<Module> findModuleByUserId(String id);

7、在ModuleDao.xml中添加对应的查询

<select id="findModuleByUserId" parameterType="java.lang.String" resultMap="BaseResultMap">
/*userid->用户角色关系表->roleid->角色模块关系表->moduleid->module信息*/
SELECT DISTINCT
m.module_id, m.parent_id, m.name, m.ctype, m.state, m.curl, m.remark
FROM
ss_module AS m,
ss_role_module AS rm,
ss_role_user AS ru
WHERE
m.module_id = rm.module_id
AND rm.role_id = ru.role_id
AND ru.user_id = #{id,jdbcType=VARCHAR}
</select>

至此：用户的角色对应的模块数据已查询出来了，后续就是要在页面进行控制展示

1.3 登陆用户菜单控制

1、找到/WEB-INF/pages/home/aside.jsp页面，添加用户菜单的展示

<!-- sidebar menu: : style can be found in sidebar.less -->
<ul class="sidebar-menu">
<li class="header">菜单</li>

<c:forEach items="${moduleList}" var="item">
<c:if test="${item.ctype==0}">
<li class="treeview">
<a href="#">
<i class="fa fa-cube"></i> <span>${item.name}</span>
<span class="pull-right-container"><i class="fa fa-angle-left pull-right"></i></span>
</a>
<ul class="treeview-menu">
<c:forEach items="${moduleList}" var="item2">
<c:if test="${item2.ctype==1 && item2.parentId == item.id}">
<li id="${item2.id}">
<a onclick="setSidebarActive(this)" href="${ctx}/${item2.curl}" target="iframe">
<i class="fa fa-circle-o"></i>${item2.name}
</a>
</li>
</c:if>
</c:forEach>
</ul>
</li>
</c:if>
</c:forEach>

2.权限校验

2.1 获取请求url

1、创建过滤器：com.itheima.web.filters.AuthorFilter

@WebFilter(value = "/*")
public class AuthorFilter implements Filter {

private FilterConfig filterConfig;

/**
* 初始化方法，获取过滤器的配置对象
* @param filterConfig
* @throws ServletException
*/
@Override
public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
}

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
//1.定义和协议相关的请求和响应对象
HttpServletRequest request ;
HttpServletResponse response;
try{
//2.把参数转换成协议相关的对象
request = (HttpServletRequest)req;
response = (HttpServletResponse)resp;

//1.获取本次操作
String url = request.getRequestURI();
String queryString = request.getQueryString();

//1.当前获取到的url： /system/dept
url = url.substring(1);
//2.当前获取到的查询参数：operation=list operation=toEdit&id=100
int index = queryString.indexOf('&');
if(index != -1){
queryString = queryString.substring(0,index);
}
url = url + "?" + queryString;

//2.获取到当前登录人允许的操作

//3.比对本次操作是否在当前登录人允许的操作范围内
//3.1如果允许，放行
//3.2不允许跳转到非法访问页

//6.放行
chain.doFilter(request,response);
}catch (Exception e){
e.printStackTrace();
}
}

@Override
public void destroy() {
//可以做一些清理操作
}
}

2.2 获取登陆用户可执行操作

1、登陆成功后需要将用户的觉得对应的模块信息存放到session，找到UserServlet中的登陆方法login，

private void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String email = request.getParameter("email");
String pwd = request.getParameter("password");
User user = userService.login(email,pwd);
if(user != null) {
request.getSession().setAttribute("loginUser", user);
//如果登录成功，加载该用户对应的角色对应的所有模块
List<Module> moduleList = userService.findModuleById(user.getId());
request.setAttribute("moduleList",moduleList);

//当前登录用户对应的可操作模块的所有url拼接成一个大的字符串
StringBuffer sbf = new StringBuffer();
for(Module m: moduleList){
sbf.append(m.getCurl());
sbf.append(',');
}
request.getSession().setAttribute("authorStr",sbf.toString());

//跳转页面
request.getRequestDispatcher("/WEB-INF/pages/home/main.jsp").forward(request, response);
}else{
response.sendRedirect(request.getContextPath()+"/login.jsp");
}
}

2、修改AuthorFilter

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
//1.定义和协议相关的请求和响应对象
HttpServletRequest request ;
HttpServletResponse response;
HttpSession session;
try{
//2.把参数转换成协议相关的对象
request = (HttpServletRequest)req;
response = (HttpServletResponse)resp;
session = request.getSession();
//1.获取本次操作
String url = request.getRequestURI();
//.css .js .png .jpg .index
if(url.endsWith(".css")
|| url.endsWith(".js")
|| url.endsWith(".png")
|| url.endsWith(".jpg")
|| url.endsWith("index.jsp")
|| url.endsWith("login.jsp")){
chain.doFilter(request,response);
return;
}
String queryString = request.getQueryString();
if(queryString.endsWith("operation=login")){
chain.doFilter(request,response);
return;
}


//1.当前获取到的url： /system/dept
url = url.substring(1);
//2.当前获取到的查询参数：operation=list operation=toEdit&id=100
int index = queryString.indexOf('&');
if(index != -1){
queryString = queryString.substring(0,index);
}
url = url + "?" + queryString;

//2.获取到当前登录人允许的操作
String authorStr = session.getAttribute("authorStr").toString();
//3.比对本次操作是否在当前登录人允许的操作范围内
//3.1如果允许，放行
//3.2不允许跳转到非法访问页

//6.放行
chain.doFilter(request,response);
}catch (Exception e){
e.printStackTrace();
}
}

2.3 权限校验

1、更改AuthorFilter，

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
HttpServletRequest request ;
HttpServletResponse response;
HttpSession session;
try{
request = (HttpServletRequest)req;
response = (HttpServletResponse)resp;
session = request.getSession();

//1.获取本次操作
String url = request.getRequestURI();
//.css .js .png .jpg .index
if(url.endsWith(".css")
|| url.endsWith(".js")
|| url.endsWith(".png")
|| url.endsWith(".jpg")
|| url.endsWith("index.jsp")
|| url.endsWith("unauthorized.jsp")
|| url.endsWith("login.jsp")){
chain.doFilter(request,response);
return;
}
String queryString = request.getQueryString();
if(queryString.endsWith("operation=login")
||queryString.endsWith("operation=home")
||queryString.endsWith("operation=logout")){
chain.doFilter(request,response);
return;
}
//1.当前获取到的url： /system/dept
url = url.substring(1);
//2.当前获取到的查询参数：operation=list operation=toEdit&id=100
int index = queryString.indexOf('&');
if(index != -1){
queryString = queryString.substring(0,index);
}
url = url + "?" + queryString;

//2.获取到当前登录人允许的操作
String authorStr = session.getAttribute("authorStr").toString();

//3.比对本次操作是否在当前登录人允许的操作范围内
if(authorStr.contains(url)){
//3.1如果允许，放行
chain.doFilter(request,response);
return;
}else{
//3.2不允许跳转到非法访问页
response.sendRedirect(request.getContextPath()+"/unauthorized.jsp");
}
}catch (Exception e){
e.printStackTrace();
}
}

2、对于页面上的元素，如果没有操作权限，我们直接让用户看不到即可，怎么操作呢？在页面上做一个判断，我们举一个例子，其他操作都是一样的

找到/WEB-INF/pages/system/user/list.jsp，

<div class="btn-group">
<c:if test="${sessionScope.authorStr.contains('system/user?operation=toAdd')}">
<button type="button" class="btn btn-default" title="新建" onclick='location.href="${ctx}/system/user?operation=toAdd"'><i class="fa fa-file-o"></i> 新建</button>
</c:if>
<button type="button" class="btn btn-default" title="删除" onclick='deleteById()'><i class="fa fa-trash-o"></i> 删除</button>
<button type="button" class="btn btn-default" title="刷新" onclick="window.location.reload();"><i class="fa fa-refresh"></i> 刷新</button>
<c:if test="${sessionScope.authorStr.contains('system/user?operation=userRoleList')}">
<button type="button" class="btn btn-default" title="角色" onclick="roleList()"><i class="fa fa-user-circle-o"></i> 角色</button>
</c:if>
</div>