springMvc注解之@ResponseBody和@RequestBody詳解

更新時(shí)間：2017年05月24日 09:15:27 作者：小嘚瑟

本篇文章主要介紹了springMvc注解之@ResponseBody和@RequestBody詳解，小編覺(jué)得挺不錯(cuò)的，現(xiàn)在分享給大家，也給大家做個(gè)參考。一起跟隨小編過(guò)來(lái)看看吧

簡(jiǎn)介

springmvc對(duì)json的前后臺(tái)傳輸做了很好封裝，避免了重復(fù)編碼的過(guò)程，下面來(lái)看看常用的@ResponseBody和@RequestBody注解

添加依賴

springmvc對(duì)json的處理依賴jackson

<dependency>
  <groupId>org.codehaus.jackson</groupId>
  <artifactId>jackson-core-asl</artifactId>
  <version>1.9.11</version>
</dependency>
<dependency>
  <groupId>org.codehaus.jackson</groupId>
  <artifactId>jackson-mapper-asl</artifactId>
  <version>1.9.11</version>
</dependency>

xml配置

<mvc:annotation-driven />//不要忘了命名空間配置

@ResponseBody

如果傳輸?shù)氖菃螌觠son對(duì)象，我們后臺(tái)可以直接用 @RequestParam接收

$.ajax({
  type : "post",
  dataType : "json",
  url : "/testRequestBody",
  data:{
    name:"韋德",
    age:35
  },
  success : function(result) {
  }
});

@RequestMapping("/testRequestBody")
public String testRequestBody(@RequestParam Map<String, Object> map) {
 System.out.println(map);// {name=韋德, age=35}
 return "index";
}

如果傳輸?shù)氖嵌鄬忧短譲son對(duì)象，這個(gè)時(shí)候會(huì)就會(huì)出現(xiàn)數(shù)據(jù)丟失問(wèn)題

@ResponseBody很好的解決了這個(gè)問(wèn)題，它會(huì)把前臺(tái)傳輸過(guò)來(lái)的json轉(zhuǎn)化為后臺(tái)對(duì)應(yīng)的對(duì)象

$.ajax({
  type : "post",
  dataType : "json",
  url : "/testRequestBody",
  contentType:"application/json",  
  data:JSON.stringify({
    name:"韋德",
    win:[2006,2012,2013],
    age:35
  }),
  success : function(result) {
  }
});

@RequestMapping("/testRequestBody")
public String testRequestBody(@RequestBody Map<String, Object> map) {
 System.out.println(map);//{name=韋德, win=[2006, 2012, 2013], age=35}
 return "index";
}

需要注意的是前臺(tái)需要指定contentType為"application/json"

同時(shí)要把json對(duì)象轉(zhuǎn)化為String，否則后臺(tái)不能識(shí)別

@ResponseBody

ajax請(qǐng)求返回json格式，往常我們可以這樣做

private void writeJson(HttpServletResponse response, Object object) {
 String json = JSON.toJSONString(object);
 response.setCharacterEncoding("UTF-8");
 response.setContentType("application/json; charset=utf-8");
 PrintWriter out = null;
 try {
  out = response.getWriter();
  out.write(json);
 } catch (IOException e) {
  e.printStackTrace();
 } finally {
  if (out != null) {
   out.close();
  }
 }
}

這個(gè)時(shí)候 @ResponseBody就派上用場(chǎng)了，只需要一個(gè)注解，全部搞定

$.ajax({
  type : "post",
  dataType : "json",
  url : "/testResponseBody",
  success : function(result) {
    console.info(result);
  }
});

@RequestMapping("/testResponseBody")
@ResponseBody
public Map<String, Object> testRequestBody() {
 Map<String, Object> result = new HashMap<String, Object>();
 result.put("name", "韋德");
 result.put("age", 35);
 return result;
}

前臺(tái)console輸出