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Spring MVC深度解析从原理到实战(最新推荐)

2025-05-14 01:43:32 186

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


    
    
        org.springframework
        spring-webmvc
        5.3.20
    
    
    
        javax.servlet
        javax.servlet-api
        4.0.1
        provided

3.2 传统xml配置 vs javaconfig

xml配置示例：



    dispatcher
    
        org.springframework.web.servlet.dispatcherservlet
    
    
        contextconfiglocation
        /web-inf/spring-mvc.xml

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" %>


    用户列表


    用户列表
    
            
        
            id
            用户名
            邮箱
        
        
                ${user.id}
                ${user.username}
                ${user.email}

id	用户名	邮箱
${user.id}	${user.username}	${user.email}

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> getallusers() {
        return responseentity.ok(userservice.findall());
    }
    @getmapping("/{id}")
    public responseentity getuserbyid(@pathvariable long id) {
        return userservice.findbyid(id)
               .map(responseentity::ok)
               .orelse(responseentity.notfound().build());
    }
    @postmapping
    public responseentity 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 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 handlevalidationexception(
            methodargumentnotvalidexception ex) {
        list 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 createuser(@requestbody userdto dto) {
    user user = userconverter.converttoentity(dto);
    // ...
}

性能优化建议：