import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Bean
public HttpMessageConverter customJackson2HttpMessageConverter() {
	return new FastJsonHttpMessageConverter4() {
		@Override
		protected void writeInternal(Object obj, Type type, HttpOutputMessage outputMessage)
				throws IOException, HttpMessageNotWritableException {
			if (obj instanceof ResultModel) {
				super.writeInternal(obj, type, outputMessage);
			} else {
				super.writeInternal(ResultResolver.sendNormalResult(obj), type, outputMessage);
			}
		}
	};
}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    FastJsonHttpMessageConverter4 converter = new FastJsonHttpMessageConverter4();
    FastJsonConfig config = new FastJsonConfig();
    config.setSerializerFeatures(SerializerFeature.WriteMapNullValue,//保留空的字段
            SerializerFeature.WriteNullStringAsEmpty,//String null -> ""
            SerializerFeature.WriteNullNumberAsZero);//Number null -> 0
    converter.setFastJsonConfig(config);
    converter.setDefaultCharset(Charset.forName("UTF-8"));
    converters.add(converter);
}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Bean
public FastJsonHttpMessageConverter4 fastJsonHttpMessageConverter4() {
    FastJsonHttpMessageConverter4 converter = new FastJsonHttpMessageConverter4();

    List<MediaType> mediaTypes = new ArrayList<>();
    mediaTypes.add(MediaType.APPLICATION_JSON_UTF8);

    converter.setSupportedMediaTypes(mediaTypes);

    return converter;
}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Bean
@ConditionalOnMissingBean({ FastJsonHttpMessageConverter4.class })
//当没有注册这个类时，自动注册Bean
public FastJsonHttpMessageConverter4 fastJsonHttpMessageConverter() {
    FastJsonHttpMessageConverter4 converter = new FastJsonHttpMessageConverter4();

    //使用最新的官方推荐配置对象的方式来注入fastjson的序列化特征
    FastJsonConfig fastJsonConfig = new FastJsonConfig();
    fastJsonConfig.setSerializerFeatures(
            SerializerFeature.WriteDateUseDateFormat,
            SerializerFeature.WriteNullListAsEmpty,
            SerializerFeature.WriteMapNullValue,
            SerializerFeature.WriteNullBooleanAsFalse,
            SerializerFeature.WriteNullStringAsEmpty
     );
    
    //添加对json值的过滤，因为像移动APP，服务端在传json值时最好不要传null，而是使用“”，这是一个演示
    ValueFilter valueFilter = new ValueFilter() {//5
        //o 是class
        //s 是key值
        //o1 是value值
        public Object process(Object o, String s, Object o1) {
            if (null == o1) {
                o1 = "";
            }
            return o1;
        }
    };
    fastJsonConfig.setSerializeFilters(valueFilter);

    converter.setFastJsonConfig(fastJsonConfig);

    return converter;
}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Override
public void registry(List<HttpMessageConverter<?>> converters) {
    FastJsonHttpMessageConverter4 fastJsonHttpMessageConverter = new FastJsonHttpMessageConverter4();
    ArrayList<MediaType> arrayList = new ArrayList<MediaType>() {{
        add(MediaType.APPLICATION_JSON_UTF8);
        add(MediaType.valueOf("text/html;charset=UTF-8"));
        add(MediaType.MULTIPART_FORM_DATA);
    }};
    fastJsonHttpMessageConverter.setSupportedMediaTypes(arrayList);
    FastJsonConfig fastJsonConfig = new FastJsonConfig();
    fastJsonConfig.setSerializerFeatures(SerializerFeature.QuoteFieldNames,
            SerializerFeature.DisableCircularReferenceDetect);
    fastJsonHttpMessageConverter.setFastJsonConfig(fastJsonConfig);
    converters.add(0, fastJsonHttpMessageConverter);
}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
public void test_1() throws Exception {

		FastJsonHttpMessageConverter4 converter = new FastJsonHttpMessageConverter4();

		Assert.assertNotNull(converter.getFastJsonConfig());
		converter.setFastJsonConfig(new FastJsonConfig());
		
		converter.canRead(VO.class, VO.class, MediaType.APPLICATION_JSON_UTF8);

		converter.canWrite(VO.class, VO.class, MediaType.APPLICATION_JSON_UTF8);
		
		Method method1 = FastJsonHttpMessageConverter4.class.getDeclaredMethod(
				"supports", Class.class);
		method1.setAccessible(true);
		method1.invoke(converter, int.class);
		
		HttpInputMessage input = new HttpInputMessage() {

			public HttpHeaders getHeaders() {
				// TODO Auto-generated method stub
				return null;
			}

			public InputStream getBody() throws IOException {
				return new ByteArrayInputStream("{\"id\":123}".getBytes(Charset
						.forName("UTF-8")));
			}

		};
		VO vo = (VO) converter.read(VO.class, VO.class, input);
		Assert.assertEquals(123, vo.getId());

		final ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
		HttpOutputMessage out = new HttpOutputMessage() {

			public HttpHeaders getHeaders() {
				return new HttpHeaders();
			}

			public OutputStream getBody() throws IOException {
				return byteOut;
			}
		};
		converter.write(vo, VO.class, MediaType.TEXT_PLAIN, out);

		byte[] bytes = byteOut.toByteArray();
		Assert.assertEquals("{\"id\":123}", new String(bytes, "UTF-8"));
		
		Method method2 = FastJsonHttpMessageConverter4.class.getDeclaredMethod(
				"readInternal", Class.class, HttpInputMessage.class);
		method2.setAccessible(true);
		method2.invoke(converter, VO.class, input);
	}
 

import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter4; //导入依赖的package包/类
@Override
public boolean supports(MethodParameter returnType, Class converterType) {
    return FastJsonHttpMessageConverter4.class.isAssignableFrom(converterType);
}