Spring MVC的常用注解

1、spring mvc的常用注解spring mvc的常用注解spring boot 默认集成了spring mvc，下面为spring mvc一些常用注解。开发环境：intellij idea 2019.2.2spring boot版本：2.1.8新建一个名称为demo的spring boot项目。一、controller注解controller注解用于修饰java类，被修饰的类充当mvc中的控制器角色。controller注解用法了component修饰，用法controller注解修饰的类，会被componentscan检测，并且会作为spring的bean被放到容器中。package c

2、om.example.demo;import org.springframework.stereotype.controller;import org.springframework.web.bind.annotation.requestmapping;import org.springframework.web.bind.annotation.responsebody;controllerpublic class democontroller requestmapping("/index") responsebody public string index

3、() return "index" 运行项目后，扫瞄器拜访：http:/localhost:8080/index，页面显示：index二、restcontroller注解restcontroller注解是为了更便利用法controller和responsebody。responsebody修饰控制器办法，办法的返回值将会被写到http的响应体中，所返回的内容不放到模型中，也不会被说明为视图的名称。下面例子等同于上面例子。package com.example.demo;import org.springframework.web.bind.annotatio

4、n.requestmapping;import org.springframework.web.bind.annotation.restcontroller;restcontrollerpublic class democontroller requestmapping("/index") public string index() return "index" 三、requestmapping注解requestmapping注解可修饰类或办法，主要用于映射哀求与处理办法。当用于修饰类并设置了url时，表示为各个哀求设置了

5、url前缀。requestmapping注解主要有以下属性：（1）path与value：用于配置映射的url；（2）method：映射的http办法，如get、post、put、delete；也可以用法默认配置了requestmapping的method属性的几个注解：getmapping等同于requestmapping(method="requestmethod.get")postmapping、putmapping、deletemapping类似。（3）params：为映射的哀求配置参数标识；（4）consumes：配置哀求的数据类型，如xml或jso

6、n等；（5）produces：配置响应的数据类型，如application/json返回json数据；package com.example.demo;import org.springframework.web.bind.annotation.getmapping;import org.springframework.web.bind.annotation.requestmapping;import org.springframework.web.bind.annotation.requestmethod;import org.springframework.web.bind.annotat

7、ion.restcontroller;restcontrollerrequestmapping("/oa")public class democontroller requestmapping(value = "/index1") public string index1() return "index1" requestmapping(value = "/index2", method = requestmethod.get) public stri

8、ng index2() return "index2" getmapping(value = "/index3") public string index3() return "index3" 扫瞄器分离拜访：http:/localhost:8080/oa/index1http:/localhost:8080/oa/index2http:/localhost:8080/oa/index3页面分离显示：index1index2index3四、pathvariable注解pathvariab

9、le注解主要用于修饰办法参数，表示该办法参数是哀求url的变量。package com.example.demo;import org.springframework.web.bind.annotation.getmapping;import org.springframework.web.bind.annotation.pathvariable;import org.springframework.web.bind.annotation.restcontroller;restcontrollerpublic class democontroller getmapping("

10、/index1/name") public string index1(pathvariable string name) return "index1: " + name; /可以为pathvariable配置属性值，显式绑定办法参数与url变量的值 getmapping("/index2/name") public string index2(pathvariable("name") string lc) return "index2: &

11、quot; + lc; 扫瞄器拜访http:/localhost:8080/index1/a页面显示：a拜访http:/localhost:8080/index1/b页面显示：b五、requestparam注解requestparam注解用于猎取哀求体中的哀求参数，如表单提交后猎取页面控件name值。package com.example.demo;import org.springframework.web.bind.annotation.postmapping;import org.springframework.web.bind.annotation.requestparam;impor

12、t org.springframework.web.bind.annotation.restcontroller;import java.util.map;restcontrollerpublic class democontroller postmapping("/index1") public string index1(requestparam string username) return username; /map存放全部哀求参数 postmapping("/index2") public string ind

13、ex2(requestparam map map) string age = map.get("age"); string sex = map.get("sex"); return age + "," + sex; 任凭在电脑中如桌面新建一个html文件： 扫瞄器打开后，假如点击提交1按钮后，页面跳到http:/localhost:8080/index1，显示abc。假如点击提交2按钮后，页面跳到http:/localhost:8080/index2，显示22,male。六、文件上传用法

14、requestparam注解可以实现文件上传。package com.example.demo;import org.springframework.web.bind.annotation.postmapping;import org.springframework.web.bind.annotation.requestparam;import org.springframework.web.bind.annotation.restcontroller;import org.springframework.web.multipart.multipartfile;import java.io.file;import java.io.ioexception;restcontrollerpublic class democontroller postmapping("/upload") public string upload(requestparam("file") multipartfile file) throws ioexception string fil