springMVC_04 Ajax请求 @RequestBody，@ResponseBody 处置JSON格式
springMVC_04 Ajax请求 @RequestBody，@ResponseBody 处理JSON格式
springMVC处理Ajax请求，返回JSON格式数据
加入对jackson的依赖，springMVC使用jackson进行JSON数据转换
<!-- json --> <dependency> <groupId>org.codehaus.jackson</groupId> <artifactId>jackson-core-asl</artifactId> <version>1.9.10</version> </dependency> <dependency> <groupId>org.codehaus.jackson</groupId> <artifactId>jackson-mapper-asl</artifactId> <version>1.9.10</version> </dependency>
Controller
package com.gc.springmvc.controller;
import java.util.ArrayList;
import java.util.List;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.gc.springmvc.model.User;
@Controller
public class AjaxController {
@RequestMapping(value="listUser")
public @ResponseBody List<User> listUser() throws Exception {
List<User> users = new ArrayList<User>();
users.add(new User("张三2", "zs"));
users.add(new User("李四", "ls"));
return users;
}
}
页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<div>
<div>
<a href="javascript:void(0)" onclick="sendAjaxReq()">Ajax请求，返回JSON数据</a>
</div>
<div id="users" style="margin-left:50%;font-weight:bold;color:red"></div>
</div>
<!-- Ajax -->
<script type="text/javascript">
function createAjaxObj() {
var req;
if (window.XMLHttpRequest) {
req = new XMLHttpRequest();
} else {
req = new ActiveXObject("Msxml2.XMLHTTP"); //ie
}
return req;
}
function sendAjaxReq() {
var req = createAjaxObj();
req.open("get", "listUser?name=王五&time="+Math.random());
req.setRequestHeader("accept", "application/json");
req.onreadystatechange = function() {
if(req.readyState=4 && req.status==200) {
var result = eval("(" + req.responseText +")");
var divNode = document.getElementById("users");
divNode.innerHTML = "";
for(var index in result) {
var name = result[index].name;
if(index>0) {
name = "<br/>" + name;
}
divNode.innerHTML += name;
}
}
}
req.send(null);
}
</script>
</body>
</html>
JSP页面中访问服务器上的静态资源，如js脚本文件
必须配置resource资源，否则按请求一个Controller进行映射处理，导致无法下载
<!-- 配置对静态资源文件的访问不被拦截，如js脚本-->
<mvc:resources location="/script/" mapping="/script/**"/>
配置文件中只需要加入如下配置，即可开启一系列功能：
<mvc:annotation-driven/>如果类路径下有jackson相关jar包，springMVC将自动注册JSON转换服务！
HttpMessageConverter support for @RequestBody method parameters and @ResponseBody method return values from @RequestMapping or @ExceptionHandler methods.
This is the complete list of HttpMessageConverters set up by mvc:annotation-driven:
ByteArrayHttpMessageConverter converts byte arrays.
StringHttpMessageConverter converts strings.
ResourceHttpMessageConverter converts to/from org.springframework.core.io.Resource for all media types.
SourceHttpMessageConverter converts to/from a javax.xml.transform.Source.
FormHttpMessageConverter converts form data to/from a MultiValueMap<String, String>.
Jaxb2RootElementHttpMessageConverter converts Java objects to/from XML — added if JAXB2 is present on the classpath.
MappingJackson2HttpMessageConverter (or MappingJacksonHttpMessageConverter) converts to/from JSON — added if Jackson 2 (or Jackson) is present on the classpath.
AtomFeedHttpMessageConverter converts Atom feeds — added if Rome is present on the classpath.
RssChannelHttpMessageConverter converts RSS feeds — added if Rome is present on the classpath.
This is the complete list of HttpMessageConverters set up by mvc:annotation-driven:
ByteArrayHttpMessageConverter converts byte arrays.
StringHttpMessageConverter converts strings.
ResourceHttpMessageConverter converts to/from org.springframework.core.io.Resource for all media types.
SourceHttpMessageConverter converts to/from a javax.xml.transform.Source.
FormHttpMessageConverter converts form data to/from a MultiValueMap<String, String>.
Jaxb2RootElementHttpMessageConverter converts Java objects to/from XML — added if JAXB2 is present on the classpath.
MappingJackson2HttpMessageConverter (or MappingJacksonHttpMessageConverter) converts to/from JSON — added if Jackson 2 (or Jackson) is present on the classpath.
AtomFeedHttpMessageConverter converts Atom feeds — added if Rome is present on the classpath.
RssChannelHttpMessageConverter converts RSS feeds — added if Rome is present on the classpath.
@RequestBody
客户端将JSON数据发送到服务端，服务端将JSON转换为对象传入@Controller
@RequestMapping(value = "/pets", method = RequestMethod.POST, consumes="application/json")
public void addPet(@RequestBody Pet pet, Model model) {
// implementation omitted
}
@ResponseBody
服务端将对象转为JSON传递到浏览器，因此，多用于get方式请求JSON数据
@Controller
@RequestMapping(value = "/pets/{petId}", method = RequestMethod.GET, produces="application/json")
@ResponseBody
public Pet getPet(@PathVariable String petId, Model model) {
// implementation omitted
}
示例:
客户端发起Ajax请求，Post方式，将JSON数据发送到服务端
服务端通过@RequestBody将JSON数据转换为对象
服务端再通过@ResponseBody将对象转换为JSON数据返回给客户端
Controller控制器
package com.gc.springmvc.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import com.gc.springmvc.model.User;
@Controller
public class AjaxController {
/**
* 接收客户端发送的JSON数据，并将其转换为对象
* @RequestBody
* 其一，从http请求报文的请求体中获取JSON数据，则说明必须是POST请求
* 其二，Body中为JSON，则最可能为Ajax请求，通过form进行post请求好像办不到呢
*/
@RequestMapping(value="jsonPost", method=RequestMethod.POST, consumes="application/json")
@ResponseBody
public User jsonPost(@RequestBody User user) {
System.out.println("ajax json post");
System.out.println(user.getName());
System.out.println(user.getPassword());
user.setName("李四");
user.setPassword("100");
return user;
}
}
JSP页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<div>
<fieldset>
<table>
<tbody>
<tr>
<td>name</td>
<td><input id="name" type=text value="张三"/></td>
</tr>
<tr>
<td>password</td>
<td><input id="password" type=password value="123"/></td>
</tr>
<tr>
<td><button id="post">ajax:POST</button></td>
</tr>
</tbody>
</table>
</fieldset>
</div>
<script type="text/javascript" src="script/jquery-1.9.1.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$("#post").click(function(){
ajaxPOST();
});
});
function ajaxPOST() {
var user = {};
user.name = $("#name").val();
user.password = $("#password").val();
var jsonStr = JSON.stringify(user);
//var json2Object = JSON.parse(jsonStr);
$.ajax({
type : "post",
contentType : "application/json;charset=UTF-8",
url : "jsonPost",
dataType : "json",
processData : false,
data : jsonStr,
success : function(msg) {
//javascript已自动将返回的json数据转为对象了
alert("success:"+msg.name+"---"+msg.password);
},
error : function() {
alert("try again!");
}
});
}
</script>
</body>
</html>