SprimgMVC：Failed to load resource: the server responded with a status of 406 (Not Acceptable)

spring
3.2.x通过@ResponseBody标签返回JSON数据的方法都报406错： Failed to load resource: the server responded with a status of 406 (Not Acceptable) 以及报错描述： The
resource identified by this request is only capable of generating responses with characteristics not acceptable according to the request "accept" headers () 于是，百度、Google了半天，发现遇到此问题的人挺多的，但是都是说什么添加Jackson什么的，我是采用的fastjson，换成Jackson尝试了半天均还是406。 后来在stackoverflow有人说是Spring
3.2的BUG，于是退回到3.1.*，不再报406了， 虽然换回3.1不报错了，但还是想看看在处理ajax返回json数据的方式上两个版本到底有何区别，debug之。 debug到org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(T returnValue,MethodParameter
returnType,ServletServerHttpRequest inputMessage,ServletServerHttpResponse outputMessage)，在以下代码处抛出了异常：

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if (compatibleMediaTypes.isEmpty()) {  
        throw new HttpMediaTypeNotAcceptableException(allSupportedMediaTypes);  
    }  

if (compatibleMediaTypes.isEmpty()) {
throw new HttpMediaTypeNotAcceptableException(allSupportedMediaTypes);
}

看来是compatibleMediaTypes为空导致。看debug信息，经过比较发现3.1的requestedMediaTypes为[*/*]，而3.2的requestedMediaTypes却为[text/html]，producibleMediaTypes都是[application/json],继而发现获取acceptableMediaTypes的方式3.1与3.2不同
3.1的

3.1的

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private List<MediaType> getAcceptableMediaTypes(HttpInputMessage inputMessage) {  
        try {  
            List<MediaType> result = inputMessage.getHeaders().getAccept();  
            return result.isEmpty() ? Collections.singletonList(MediaType.ALL) : result;  
        } catch (IllegalArgumentException ex) {  
            if (logger.isDebugEnabled()) {  
                logger.debug("Could not parse Accept header: " + ex.getMessage());  
            }  
            return Collections.emptyList();  
        }  
    }  

private List<MediaType> getAcceptableMediaTypes(HttpInputMessage inputMessage) {
        try {
            List<MediaType> result = inputMessage.getHeaders().getAccept();
            return result.isEmpty() ? Collections.singletonList(MediaType.ALL) : result;
        } catch (IllegalArgumentException ex) {
            if (logger.isDebugEnabled()) {
                logger.debug("Could not parse Accept header: " + ex.getMessage());
            }
            return Collections.emptyList();
        }
    }

3.2的

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private List<MediaType> getAcceptableMediaTypes(HttpServletRequest request) throws HttpMediaTypeNotAcceptableException {  
        List<MediaType> mediaTypes = this.contentNegotiationManager.resolveMediaTypes(new ServletWebRequest(request));  
        return mediaTypes.isEmpty() ? Collections.singletonList(MediaType.ALL) : mediaTypes;  
    }  

private List<MediaType> getAcceptableMediaTypes(HttpServletRequest request) throws HttpMediaTypeNotAcceptableException {
        List<MediaType> mediaTypes = this.contentNegotiationManager.resolveMediaTypes(new ServletWebRequest(request));
        return mediaTypes.isEmpty() ? Collections.singletonList(MediaType.ALL) : mediaTypes;
    }

看来问题就是出在这里了。不知Spring为何改变该实现方式？？！！ 

解决方法如下：

一、第一种 继续用Spring 3.1.4。

二、第二种

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<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"  
    xmlns:mvc="http://www.springframework.org/schema/mvc"  
       
        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/aop  
             http://www.springframework.org/schema/aop/spring-aop-3.0.xsd  
             http://www.springframework.org/schema/tx   
             http://www.springframework.org/schema/tx/spring-tx-3.0.xsd  
             http://www.springframework.org/schema/mvc    
             http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">  

<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:mvc="http://www.springframework.org/schema/mvc"

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/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">[/code] 把spring-mvc-3.0.xsd 升级到 spring-mvc-3.2.xsd

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<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"  
xmlns:mvc="http://www.springframework.org/schema/mvc"  
  
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/aop  
         http://www.springframework.org/schema/aop/spring-aop-3.0.xsd  
         http://www.springframework.org/schema/tx   
         http://www.springframework.org/schema/tx/spring-tx-3.0.xsd  
        http://www.springframework.org/schema/mvc   
        http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">  

<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:mvc="http://www.springframework.org/schema/mvc"

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/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">[/code] 
然后把<mvc:annotation-driven>修改成如下格式

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<mvc:annotation-driven content-negotiation-manager="contentNegotiationManager" />   
<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">   
    <property name="favorPathExtension" value="false" />  
    <property name="favorParameter" value="false" />   
    <property name="ignoreAcceptHeader" value="false" />   
    <property name="mediaTypes" >   
        <value>  
            atom=application/atom+xml  
            html=text/html  
            json=application/json  
            *=*/*  
        </value>   
    </property>  
</bean>  

<mvc:annotation-driven content-negotiation-manager="contentNegotiationManager" />
<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
<property name="favorPathExtension" value="false" />
<property name="favorParameter" value="false" />
<property name="ignoreAcceptHeader" value="false" />
<property name="mediaTypes" >
<value>
atom=application/atom+xml
html=text/html
json=application/json
*=*/*
</value>
</property>
</bean>
三、第三种

详情见下面的地址点击打开链接

四、第四种

spring 3.2时requestedMediaTypes却为[text/html]的情况报406错误，还有一个原因可能是由于采用的后缀有关，如果使用*.htm,*.html等，默认就会采用[text/html]编码，若改成*.json,*.shtml等就OK