SpringMVC 3.1下返回json时中文显示乱码问题的解决方案

Spring返回json时中文显示乱码的问题，网络上大多数的方法在Spring 3.1下都失效了。搞不懂Spring怎么不修正这个问题呢？

多费周折最终还是找到解决方案，并亲测通过，故分享之。

简单的说就是新建个转换类再注入。就那么简单，这就是开源的好处啊！

配置：

 <mvc:annotation-driven>  
   <mvc:message-converters register-defaults="true">
     <bean class="com.abc.spring.UTF8StringHttpMessageConverter"/>   </mvc:message-converters> 
</mvc:annotation-driven>

public class UTF8StringHttpMessageConverter extends

        AbstractHttpMessageConverter<String> {

    public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");

    private final List<Charset> availableCharsets;

    public UTF8StringHttpMessageConverter() {

        this(DEFAULT_CHARSET);

    }

    public UTF8StringHttpMessageConverter(Charset defaultCharset) {

        super(new MediaType("text", "plain", defaultCharset), MediaType.ALL);

        this.availableCharsets = new ArrayList<Charset>(Charset

                .availableCharsets().values());

    }

    @Override

    protected boolean supports(Class<?> clazz) {

        return String.class.equals(clazz);

    }

    @Override

    protected String readInternal(Class<? extends String> clazz,

            HttpInputMessage inputMessage) throws IOException,

            HttpMessageNotReadableException {

        MediaType contentType = inputMessage.getHeaders().getContentType();

        Charset charset = contentType.getCharSet() != null ? contentType

                .getCharSet() : DEFAULT_CHARSET;

        return FileCopyUtils.copyToString(new InputStreamReader(inputMessage

                .getBody(), charset));

    }

    @Override

    protected void writeInternal(String t, HttpOutputMessage outputMessage)

            throws IOException, HttpMessageNotWritableException {

MediaType contentType = outputMessage.getHeaders().getContentType();

        Charset charset = contentType.getCharSet() != null ? contentType

                .getCharSet() : DEFAULT_CHARSET;

        FileCopyUtils.copy(t, new OutputStreamWriter(outputMessage.getBody(),

                charset));

    }

    protected List<Charset> getAcceptedCharsets() {

        return this.availableCharsets;

    }

    

    @Override

    protected Long getContentLength(String s, MediaType contentType) {

        if (contentType != null && contentType.getCharSet() != null) {

            Charset charset = contentType.getCharSet();

            try {

                return (long) s.getBytes(charset.name()).length;

            } catch (UnsupportedEncodingException ex) {                

                throw new InternalError(ex.getMessage());

            }

        } else {

            return null;

        }

    }

}

 或者：

<bean  class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" >   

    <property name="messageConverters">   

         <list>   

             <bean class = "org.springframework.http.converter.StringHttpMessageConverter">   

                <property name = "supportedMediaTypes">   

                     <list>   

                         <value>text/plain;charset=UTF-8</value>   

                     </list>   

                </property>   

             </bean>   

         </list>   

    </property>   

</bean>   

参考：http://www.myexception.cn/h/709115.html