WebMvcConfigurationSupport和WebMvcConfigurer的区别

1、WebMvcConfigurationSupport的出现

springboot2.0之后配置拦截器extends 的WebMvcConfigurerAdapter过时，取而代之的是WebMvcConfigurationSupport。WebMvcConfigurerAdapter只是对WebMvcCofigurer的空实现,而WebMvcConfigurationSupport的实现的方法更全面

2、注意点

继承WebMvcConfigurationSupport会发现Spring Boot的WebMvc自动配置失效(WebMvcAutoConfiguration自动化配置)。
导致无法视图解析器无法解析并返回到对应的视图。

3、示例

package com.hsshy.beam.config;
import com.alibaba.fastjson.serializer.ToStringSerializer;
import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.serializer.ValueFilter;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
import java.math.BigInteger;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;

@Configuration
public class WebCatMvcConfiguration extends WebMvcConfigurationSupport {

    @Override
    protected void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter();
        converter.setFastJsonConfig(fastjsonConfig());
        converter.setSupportedMediaTypes(getSupportedMediaType());
    }

    /**
     * fastjson的配置
     */
    public FastJsonConfig fastjsonConfig() {
        FastJsonConfig fastJsonConfig = new FastJsonConfig();
        fastJsonConfig.setSerializerFeatures(
                SerializerFeature.PrettyFormat,
                SerializerFeature.WriteMapNullValue,
                SerializerFeature.WriteEnumUsingToString
        );
        fastJsonConfig.setDateFormat("yyyy-MM-dd HH:mm:ss");
        ValueFilter valueFilter = new ValueFilter() {
            public Object process(Object o, String s, Object o1) {
                if (null == o1) {
                    o1 = "";
                }
                return o1;
            }
        };
        fastJsonConfig.setCharset(Charset.forName("utf-8"));
        fastJsonConfig.setSerializeFilters(valueFilter);

        //解决Long转json精度丢失的问题
        SerializeConfig serializeConfig = SerializeConfig.globalInstance;
        serializeConfig.put(BigInteger.class, ToStringSerializer.instance);
        serializeConfig.put(Long.class, ToStringSerializer.instance);
        serializeConfig.put(Long.TYPE, ToStringSerializer.instance);
        fastJsonConfig.setSerializeConfig(serializeConfig);
        return fastJsonConfig;
    }

    /**
     * 支持的mediaType类型
     */
    public List<MediaType> getSupportedMediaType() {
        ArrayList<MediaType> mediaTypes = new ArrayList<>();
        mediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
        return mediaTypes;
    }
}