1. springMVC基本功能

与servlet技术功能相等,实现表现层开发:

(1) maven坐标导入

  <dependencies><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>6.0.11</version></dependency><dependency><groupId>jakarta.servlet</groupId><artifactId>jakarta.servlet-api</artifactId><version>5.0.0</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.13.2</version><scope>test</scope></dependency></dependencies>

(2) 编写表现层

@Controller         // 使用controller定义bean
public class test {@GetMapping("/hello")@ResponseBody		// 直接返回给浏览器public String testMVC(){System.out.println("接收到请求");return "hello world!";}
}

(3) springMVC配置类编写

容器配置:

package com.xjy.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan({"com.xjy.controller"})
public class MvcConfig {
}

定义 Spring MVC应用程序的初始化器:

package com.xjy.config;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.support.AbstractDispatcherServletInitializer;
public class MvcContainerInit extends AbstractDispatcherServletInitializer {
//创建DispatcherServlet的应用程序上下文（ApplicationContext）@Overrideprotected WebApplicationContext createServletApplicationContext() {AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();ctx.register(MvcConfig.class);return ctx;}//指定DispatcherServlet的映射路径@Overrideprotected String[] getServletMappings() {return new String[]{"/"};}@Overrideprotected WebApplicationContext createRootApplicationContext() {return null;}public WebApplicationContext context(){return this.createServletApplicationContext();}
}

(4) 部署tomcat访问

注意对应的版本:

部署tomcat程序:

启动程序后浏览器访问:

2. 各种请求方法

get请求

    @GetMapping("/get") // 接受get请求@ResponseBodypublic String get(){System.out.println("接受到请求");return "get";}

post请求

        @PostMapping("/post")@ResponseBodypublic String post(){System.out.println("接受到请求");return "post";}

put请求

    @PutMapping("/put")@ResponseBodypublic String put(){System.out.println("接受到请求");return "put";}

delete请求

    @DeleteMapping("/delete")@ResponseBodypublic String delete(){System.out.println("接受到请求");return "delete";}

请求参数提取

@Controller
@RequestMapping("/user")
public class userController {@RequestMapping("/hello")@ResponseBodypublic String save(){System.out.println("接受到请求");return "hello word!";}}

访问:

3. 请求参数接收

(1) param参数接受

直接参数接收:

    @GetMapping("/get")@ResponseBodypublic String get(int id){System.out.println("接受到请求"+id);return "get";}

封装到对象中

    @GetMapping("/get")@ResponseBodypublic String get(student stu){System.out.println("接受到请求"+stu.getName()+stu.getAge());return "get";}

发送请求:

(2) 路劲参数接收

    @GetMapping("/get/{id}")@ResponseBodypublic String get(@PathVariable int id){System.out.println("接受到路劲参数:"+id);return "get";}

发送请求:

集合接受

    @PostMapping("/post")@ResponseBodypublic String post(@RequestParam List<Integer> list){System.out.println("接受到请求"+list.get(0));return "ok";}

发送请求:

时间类型接收

    @GetMapping("/get")@ResponseBodypublic String get(@DateTimeFormat(pattern = "yyyy-MM-dd") LocalDate date){System.out.println("接受到时间参数:"+date);return "get";}

发送:

json参数接收

maven导包

    <dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.13.3</version></dependency>

开启功能

@Configuration
@ComponentScan({"com.xjy.controller"})
@EnableWebMvc
public class MvcConfig {
}

接收数据

    @PostMapping("/post")@ResponseBodypublic String post(@RequestBody student stu){System.out.println("接受到请求"+ stu.getName());return "{'status','ok'}";}

发送数据:

4. 响应数据

方法中直接return

返回json: @ResponseBody 加上注解
@RestController -> @controller + @ResponseBody

5. 全局异常处理

注解需要配包扫描:

@RestControllerAdvice
public class GlobalExceptionHandler {@ExceptionHandler(Exception.class)public String exceptionHandler(Exception ex){System.out.println("处理到异常");return "err";}
}

模拟异常:

6. springMvc拦截器(Interceptor)

自定义拦截:

public class interceptorDo implements HandlerInterceptor {@Override // 拦截方法public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {System.out.println("拦截到请求");return true;//返回true放行,返回不放行;}@Override  //资源运行后执行public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);}@Override  //视图渲染完毕后执行public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {HandlerInterceptor.super.afterCompletion(request, response, handler, ex);}
}

配置拦截器:

@Configuration
@ComponentScan({"com.xjy.controller"})
@EnableWebMvc       
public class MvcConfig implements WebMvcConfigurer {@Beanpublic interceptorDo getInteceptor(){return new interceptorDo();}@Autowiredprivate interceptorDo interceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(interceptor).excludePathPatterns("/long");//过滤登录拦截}
}