get请求
在Controller中--->从仓库里取出要用的mysql----->对于get请求（httpsession,model容器）----->从httpsession取出userid再赋值给userid----->用userid在mysql获取用户的信息------>然后用户的信息在保存在model容器里---->return到html地址里面
put请求
得到请求体的参数--->从httpsession取出userid再赋值给userid----->根据用户id查找数据库----->更新user_id里面的数据------>保存到数据库里面-----return ResponseEntity.ok
Thymeleaf 语法解释
<span th:text="${user.username}"></span>
<a th:href="@{/profile/{id}(id=${user.id})}">View Profile</a>
<img th:src="@{${user.profilePictureUrl}}" alt="User Profile Picture"/>
<img th:src="@{${user.profilePictureUrl}}" alt="User Profile Picture"/>
<div th:class="${user.active} ? 'active' : 'inactive'">User Profile</div>
<p th:if="${user.isActive}">User is active</p>
<p th:unless="${user.isActive}">User is inactive</p>
<ul>
<li th:each="user : ${users}" th:text="${user.username}"></li>
</ul>
<form th:action="@{/submit}" th:object="${user}">
<input type="text" th:field="*{username}" />
<input type="password" th:field="*{password}" />
<button type="submit">Submit</button>
</form>
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