Spring mvc ContentNegotiatingViewResolver 根據路徑後綴，選擇不同視圖

ContentNegotiatingViewResolver  實現了同一資源，多種表述。這個視圖解析器允許使用同樣的內容數據來呈現不同的view。

ContentNegotiatingViewResolver是根據客戶提交的MimeType(如 text/html,application/xml)來跟服務端的一組viewResover的MimeType相比較,如果符合,即返回viewResover的數據.而 /user.xml，ContentNegotiatingViewResolver會首先將 .xml 根據mediaTypes屬性將其轉換成 application/xml,然後完成前面所說的比較.

方法一：使用擴展名

http://localhost:8080/learn/user.xml 獲取xml類型數據

http://localhost:8080/learn/user.json  獲取json類型數據

http://localhost:8080/learn/user  使用默認view呈現，如jsp

方法二：使用http 請求頭的Accept

GET /user HTTP/1.1

Accept:application/xml

GET /user HTTP/1.1

Accept:application/json

方法三：使用參數

http://localhost:8080/learn/user?format=xml

http://localhost:8080/learn/user?format=json

示例：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:aop="http://www.springframework.org/schema/aop"
	xsi:schemaLocation="
		http://www.springframework.org/schema/beans	http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
		http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
	<!-- 使用spring mvc -->
        <mvc:annotation-driven />  

	<!-- 使用annotation 自動註冊bean,並保證@Required,@Autowired的屬性被注入 -->
	<context:component-scan base-package="com.learn" />

	<!-- 同一資源，多種表述 -->
	<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
		<!-- 是否啓用擴展名支持，默認爲true -->
		<property name="favorPathExtenion" value="true" />
		<!-- 是否啓用參數支持，默認爲true -->
		<property name="favorParameter" value="false" />
		<!-- 是否忽略掉accept header,默認爲false -->
		<property name="ignoreAcceptHeader" value="true" />
		
		<!-- 擴展名到mimeType的映射 -->
		<property name="mediaTypes">
			<map>
				<!-- 例如：/user.json 中的 .json 會映射到 application/json -->
                <entry key="json" value="application/json" />
                <entry key="xml" value="application/xml" />        
            </map>
		</property>
		
		<!-- 如果所有mediaType都沒匹配上，就使用defaultContentType -->
		<property name="defaultContentType" value="text/html"/>
	</bean>
	
	<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
		<!-- 解析器的執行順序 -->
		<property name="order" value="1" />
		<property name="contentNegotiationManager" ref="contentNegotiationManager" />
		
		<property name="defaultViews">
			<list>
				<bean class="org.springframework.web.servlet.view.json.MappingJackson2JsonView"></bean>
				<bean class="org.springframework.web.servlet.view.xml.MarshallingView">
					<constructor-arg>
						<bean class="org.springframework.oxm.jaxb.Jaxb2Marshaller">
							<property name="classesToBeBound">
								<list>
									<value>com.learn.model.User</value>
								</list>
							</property>
						</bean>
					</constructor-arg>
				</bean>
			</list>
		</property>
		
	</bean>
	<!-- 上面沒匹配到則會使用這個視圖解析器 ,解析爲jsp  -->
	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="order" value="2" />
		<property name="prefix" value="/" /> 
		<property name="suffix" value=".jsp"/>
	</bean>

</beans>

實體類：

package com.learn.model;
import javax.xml.bind.annotation.XmlRootElement;

// 獲取xml類型時，必須要添加
@XmlRootElement(name="user")
public class User {

	private String userName;
	private String age;
	private String sex;
	
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public String getUserName() {
		return userName;
	}
	public void setUserName(String userName) {
		this.userName = userName;
	}
	public String getAge() {
		return age;
	}
	public void setAge(String age) {
		this.age = age;
	}
}

Controller類：

package com.learn.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;

import com.learn.model.User;

@Controller
public class Resource {
	
	@RequestMapping(value="/user")
	public String queryUser(User user, ModelMap model)
	{
		User u = user;
		u.setSex("man");
		model.addAttribute("user", u);
		
		return "user";
	}

}

jsp文件：

<%@ 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>
<body>
    UserName: ${requestScope.user.userName } <br/>
    Age: ${requestScope.user.age } <br/>
    Sex: ${requestScope.user.sex }
  </body>
</body>
</html>

參考文章：http://blog.csdn.net/z69183787/article/details/41654603#php