springboot2.0 controller中文问号或者乱码的解决办法

开发过程中中文一直是？？？显示，根据网上的帖子修改配置文件后也没有效果。后来偶然间看到一篇文章，把fastjson改为默认序列化插件，加入后就没有问题了。

package com.leenleda.ward.tv.admin.interceptor;

import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import com.leenleda.ward.tv.common.config.LeenledaConfig;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;


/**
 * @Author: pengbenlei
 * @Date: 2020/2/19 11:22
 * @Description:
 */
@Configuration
@EnableWebMvc
public class CustomMVCConfiguration implements WebMvcConfigurer {

    @Resource
    LoginInterceptor loginInterceptor;

    @Autowired
    LeenledaConfig leenledaConfig;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //登录拦截器
        registry.addInterceptor(loginInterceptor).addPathPatterns("/admin/**").excludePathPatterns(Arrays.asList("/file/**"));
    }

    /**
     * 添加静态资源文件，外部可以直接访问地址
     *
     * @param registry
     */
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        String locationPath = "file:" + leenledaConfig.getLeenledaUploadRoot() + "/leenleda/application/";
        registry.addResourceHandler("/file/**")
                .addResourceLocations(locationPath);
    }

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {

        for (int i = converters.size() - 1; i >= 0; i--) {
            if (converters.get(i) instanceof MappingJackson2HttpMessageConverter) {
                converters.remove(i);
            }
        }
        FastJsonHttpMessageConverter fastJsonHttpMessageConverter = new FastJsonHttpMessageConverter();
        FastJsonConfig config = new FastJsonConfig();
        config.setSerializerFeatures(
                SerializerFeature.WriteMapNullValue,        // 是否输出值为null的字段,默认为false
                SerializerFeature.WriteNullListAsEmpty,     // 将Collection类型字段的字段空值输出为[]
                SerializerFeature.WriteNullStringAsEmpty,   // 将字符串类型字段的空值输出为空字符串
                SerializerFeature.WriteNullNumberAsZero,    // 将数值类型字段的空值输出为0
                SerializerFeature.WriteDateUseDateFormat,
                SerializerFeature.DisableCircularReferenceDetect    // 禁用循环引用
        );
        fastJsonHttpMessageConverter.setFastJsonConfig(config);
        // 添加支持的MediaTypes;不添加时默认为*/*,也就是默认支持全部
        // 但是MappingJackson2HttpMessageConverter里面支持的MediaTypes为application/json
        // 参考它的做法, fastjson也只添加application/json的MediaType
        List<MediaType> fastMediaTypes = new ArrayList<>();
        fastMediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
        fastJsonHttpMessageConverter.setSupportedMediaTypes(fastMediaTypes);
        converters.add(fastJsonHttpMessageConverter);
    }

}