
一、spring mvc概述
1.1 mvc设计模式
mvc(model-view-controller)是一种经典的软件架构模式,将应用程序分为三个核心组件:
- model:数据模型,负责业务逻辑和数据管理
- view:视图层,负责数据展示
- controller:控制器,处理用户请求并协调model和view
1.2 spring mvc特点
- 基于dispatcherservlet的前端控制器模式
- 灵活的配置方式(注解驱动)
- 强大的数据绑定和验证机制
- 支持多种视图技术(jsp、thymeleaf等)
- 与spring框架无缝集成
二、spring mvc核心组件
2.1 架构流程图解
[客户端] --> [dispatcherservlet]
--> [handlermapping]
--> [controller]
--> [modelandview]
--> [viewresolver]
--> [视图]2.2 核心组件说明
- dispatcherservlet:前端控制器,统一处理请求
- handlermapping:请求到处理器的映射
- controller:业务逻辑处理器
- viewresolver:视图解析器
- handleradapter:处理器适配器
- model:数据模型容器
三、环境搭建与配置
3.1 maven依赖
<dependencies>
<!-- spring mvc -->
<dependency>
<groupid>org.springframework</groupid>
<artifactid>spring-webmvc</artifactid>
<version>5.3.20</version>
</dependency>
<!-- servlet api -->
<dependency>
<groupid>javax.servlet</groupid>
<artifactid>javax.servlet-api</artifactid>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
</dependencies>3.2 传统xml配置 vs javaconfig
xml配置示例:
<!-- web.xml -->
<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>
org.springframework.web.servlet.dispatcherservlet
</servlet-class>
<init-param>
<param-name>contextconfiglocation</param-name>
<param-value>/web-inf/spring-mvc.xml</param-value>
</init-param>
</servlet>javaconfig实现:
@configuration
@enablewebmvc
@componentscan("com.example.controller")
public class webconfig implements webmvcconfigurer {
@bean
public viewresolver viewresolver() {
internalresourceviewresolver resolver = new internalresourceviewresolver();
resolver.setprefix("/web-inf/views/");
resolver.setsuffix(".jsp");
return resolver;
}
}四、控制器开发实践
4.1 基础控制器示例
@controller
@requestmapping("/user")
public class usercontroller {
@getmapping("/profile")
public string showprofile(model model) {
user user = userservice.getcurrentuser();
model.addattribute("user", user);
return "profile";
}
@postmapping("/update")
public string updateprofile(@valid userform form,
bindingresult result) {
if (result.haserrors()) {
return "edit-profile";
}
userservice.updateuser(form);
return "redirect:/user/profile";
}
}4.2 请求映射注解
@requestmapping:通用请求映射@getmapping/@postmapping:特定http方法映射@pathvariable:url模板变量@requestparam:请求参数绑定
@getmapping("/articles/{id}")
public string getarticle(@pathvariable long id,
@requestparam(defaultvalue = "desc") string sort,
model model) {
// 业务逻辑
return "article-detail";
}
五、数据处理与绑定
5.1 表单处理示例
@controller
@requestmapping("/product")
public class productcontroller {
@getmapping("/create")
public string showform(model model) {
model.addattribute("product", new product());
return "product-form";
}
@postmapping("/save")
public string saveproduct(@modelattribute("product") product product,
bindingresult result) {
if (result.haserrors()) {
return "product-form";
}
productservice.save(product);
return "redirect:/product/list";
}
}5.2 数据验证
public class product {
@notblank(message = "产品名称不能为空")
@size(max = 50, message = "名称长度不能超过50字符")
private string name;
@min(value = 0, message = "价格不能为负数")
private bigdecimal price;
// getters/setters
}六、视图技术集成
6.1 thymeleaf配置
@configuration
@enablewebmvc
public class thymeleafconfig {
@bean
public springresourcetemplateresolver templateresolver() {
springresourcetemplateresolver resolver = new springresourcetemplateresolver();
resolver.setprefix("/web-inf/views/");
resolver.setsuffix(".html");
resolver.settemplatemode("html5");
resolver.setcharacterencoding("utf-8");
return resolver;
}
@bean
public springtemplateengine templateengine() {
springtemplateengine engine = new springtemplateengine();
engine.settemplateresolver(templateresolver());
return engine;
}
}6.2 jsp视图示例
<%@ page contenttype="text/html;charset=utf-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>用户列表</title>
</head>
<body>
<h2>用户列表</h2>
<table>
<tr>
<th>id</th>
<th>用户名</th>
<th>邮箱</th>
</tr>
<c:foreach items="${users}" var="user">
<tr>
<td>${user.id}</td>
<td>${user.username}</td>
<td>${user.email}</td>
</tr>
</c:foreach>
</table>
</body>
</html>七、restful api开发

7.1 rest控制器
@restcontroller
@requestmapping("/api/users")
public class userapicontroller {
@autowired
private userservice userservice;
@getmapping
public responseentity<list<user>> getallusers() {
return responseentity.ok(userservice.findall());
}
@getmapping("/{id}")
public responseentity<user> getuserbyid(@pathvariable long id) {
return userservice.findbyid(id)
.map(responseentity::ok)
.orelse(responseentity.notfound().build());
}
@postmapping
public responseentity<user> createuser(@requestbody @valid user user) {
user saveduser = userservice.save(user);
return responseentity.created(uri.create("/api/users/" + saveduser.getid()))
.body(saveduser);
}
}
八、高级特性

8.1 拦截器实现
public class authinterceptor implements handlerinterceptor {
@override
public boolean prehandle(httpservletrequest request,
httpservletresponse response,
object handler) throws exception {
if (request.getsession().getattribute("user") == null) {
response.sendredirect("/login");
return false;
}
return true;
}
}
// 注册拦截器
@configuration
public class webconfig implements webmvcconfigurer {
@override
public void addinterceptors(interceptorregistry registry) {
registry.addinterceptor(new authinterceptor())
.addpathpatterns("/**")
.excludepathpatterns("/login", "/register");
}
}8.2 全局异常处理
@controlleradvice
public class globalexceptionhandler {
@exceptionhandler(resourcenotfoundexception.class)
public responseentity<errorresponse> handlenotfound(resourcenotfoundexception ex) {
errorresponse error = new errorresponse();
error.settimestamp(localdatetime.now());
error.setstatus(httpstatus.not_found.value());
error.setmessage(ex.getmessage());
return new responseentity<>(error, httpstatus.not_found);
}
@exceptionhandler(methodargumentnotvalidexception.class)
public responseentity<errorresponse> handlevalidationexception(
methodargumentnotvalidexception ex) {
list<string> errors = ex.getbindingresult()
.getfielderrors()
.stream()
.map(fielderror::getdefaultmessage)
.collect(collectors.tolist());
errorresponse error = new errorresponse();
error.setstatus(httpstatus.bad_request.value());
error.setmessage("validation failed");
error.setdetails(errors);
return new responseentity<>(error, httpstatus.bad_request);
}
}九、最佳实践建议
遵循分层架构原则:
- controller层保持精简
- 业务逻辑放在service层
- 数据访问使用repository模式
使用dto进行数据传输:
public class userdto {
private string username;
private string email;
// 省略getter/setter
}
@postmapping
public responseentity<user> createuser(@requestbody userdto dto) {
user user = userconverter.converttoentity(dto);
// ...
}性能优化建议:
- 合理使用缓存(@cacheable)
- 启用gzip压缩
- 异步处理(@async)
安全注意事项:
- 使用csrf保护
- 输入验证和输出编码
- 参数化查询防止sql注入
十、常见问题排查
404错误排查步骤:
- 检查@requestmapping注解路径
- 确认视图解析器配置
- 查看组件扫描范围
数据绑定失败处理:
- 检查字段名称是否匹配
- 验证数据类型是否兼容
- 使用@initbinder进行自定义绑定
性能问题分析:
- 使用spring actuator监控端点
- 分析数据库查询性能
- 检查视图渲染时间
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