Spring Boot实现全局序列化配置（Jackson、FastJson）

        
        
            cn.hutool
            hutool-all
            5.4.2
        
        
        
            com.alibaba
            fastjson
            1.2.47
        

        具体步骤请查看以下博客。

Jackson 全局序列化配置的2种实现方式（@Bean注解创建ObjectMapper、重写configureMessageConverters方法）https://blog.csdn.net/qq_38974638/article/details/120529468

        全局序列化配置类。

package com.config;

import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import com.serializer.CustomCollectionSerializer;
import com.serializer.CustomDateSerializer;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;


@Configuration
@EnableWebMvc
public class JsonConfig implements WebMvcConfigurer {
    
    @Override
    public void configureMessageConverters(List> converters) {
        //fastjson的全局序列化方式
        configureFastJsonHttpMessageConverter(converters);
    }

    
    private void configureFastJsonHttpMessageConverter(List> converters) {
        // 定义一个convert转换消息的对象；
        FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
        //配置Content-Type
        List supportedMediaTypes = new ArrayList<>();
        supportedMediaTypes.add(MediaType.APPLICATION_JSON);
        supportedMediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
        supportedMediaTypes.add(MediaType.APPLICATION_ATOM_XML);
        supportedMediaTypes.add(MediaType.APPLICATION_FORM_URLENCODED);
        supportedMediaTypes.add(MediaType.APPLICATION_OCTET_STREAM);
        supportedMediaTypes.add(MediaType.APPLICATION_PDF);
        supportedMediaTypes.add(MediaType.APPLICATION_RSS_XML);
        supportedMediaTypes.add(MediaType.APPLICATION_XHTML_XML);
        supportedMediaTypes.add(MediaType.APPLICATION_XML);
        supportedMediaTypes.add(MediaType.IMAGE_GIF);
        supportedMediaTypes.add(MediaType.IMAGE_JPEG);
        supportedMediaTypes.add(MediaType.IMAGE_PNG);
        supportedMediaTypes.add(MediaType.TEXT_EVENT_STREAM);
        supportedMediaTypes.add(MediaType.TEXT_HTML);
        supportedMediaTypes.add(MediaType.TEXT_MARKDOWN);
        supportedMediaTypes.add(MediaType.TEXT_PLAIN);
        supportedMediaTypes.add(MediaType.TEXT_XML);
        fastConverter.setSupportedMediaTypes(supportedMediaTypes);
        // 添加fastjson的配置信息
        FastJsonConfig fastJsonConfig = new FastJsonConfig();
        fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat,
                SerializerFeature.WriteMapNullValue,
                SerializerFeature.WriteNullStringAsEmpty,
                SerializerFeature.WriteNullListAsEmpty,
                SerializerFeature.DisableCircularReferenceDetect,
                SerializerFeature.WriteNonStringKeyAsString
        );
        SerializeConfig serializeConfig = SerializeConfig.globalInstance;
        serializeConfig.put(Long.class, com.alibaba.fastjson.serializer.ToStringSerializer.instance);
        serializeConfig.put(Long.TYPE, com.alibaba.fastjson.serializer.ToStringSerializer.instance);
        serializeConfig.put(Date.class, new CustomDateSerializer());
        serializeConfig.put(ArrayList.class, new CustomCollectionSerializer());
        fastJsonConfig.setSerializeConfig(serializeConfig);
        // convert添加配置信息.
        fastConverter.setFastJsonConfig(fastJsonConfig);
        // 将convert添加到converters当中.
        converters.add(fastConverter);
    }
}

         自定义Date序列化类。

package com.serializer;

import cn.hutool.core.date.DateUtil;
import com.alibaba.fastjson.serializer.DateCodec;
import com.alibaba.fastjson.serializer.JSONSerializer;
import com.alibaba.fastjson.serializer.SerializeWriter;

import java.io.IOException;
import java.lang.reflect.Type;
import java.util.Date;


public class CustomDateSerializer extends DateCodec {
    
    public void write(JSonSerializer serializer, Object object, Object fieldName, Type fieldType, int features) throws IOException {
        SerializeWriter out = serializer.getWriter();
        if (object == null) {
            out.writeNull();
            return;
        }
        //指定日期格式
        out.writeString(DateUtil.format((Date) object, "yyyy-MM-dd HH:mm:ss"));
        return;
    }
}

        自定义集合序列化类。

package com.serializer;

import com.alibaba.fastjson.serializer.*;
import com.alibaba.fastjson.util.TypeUtils;

import java.io.IOException;
import java.lang.reflect.Type;
import java.util.*;


public class CustomCollectionSerializer extends CollectionCodec {
    
    public void write(JSonSerializer serializer, Object object, Object fieldName, Type fieldType, int features) throws IOException {
        SerializeWriter out = serializer.out;

        if (object == null) {
            out.writeNull(SerializerFeature.WriteNullListAsEmpty);
            return;
        }

        Type elementType = null;
        if (out.isEnabled(SerializerFeature.WriteClassName)
                || SerializerFeature.isEnabled(features, SerializerFeature.WriteClassName)) {
            elementType = TypeUtils.getCollectionItemType(fieldType);
        }

        Collection collection = (Collection) object;

        SerialContext context = serializer.getContext();
        serializer.setContext(context, object, fieldName, 0);

        if (out.isEnabled(SerializerFeature.WriteClassName)) {
            if (HashSet.class == collection.getClass()) {
                out.append("Set");
            } else if (TreeSet.class == collection.getClass()) {
                out.append("TreeSet");
            }
        }

        try {
            int i = 0;
            out.append('[');
            for (Object item : collection) {

                if (i++ != 0) {
                    out.append(',');
                }

                if (item == null) {
                    out.writeNull();
                    continue;
                }

                Class clazz = item.getClass();
                ObjectSerializer itemSerializer = serializer.getObjectWriter(clazz);
                if (SerializerFeature.isEnabled(features, SerializerFeature.WriteClassName)
                        && itemSerializer instanceof JavaBeanSerializer) {
                    JavaBeanSerializer javaBeanSerializer = (JavaBeanSerializer) itemSerializer;
                    javaBeanSerializer.writeNoneASM(serializer, item, i - 1, elementType, features);
                } else {
                    itemSerializer.write(serializer, item, i - 1, elementType, features);
                }
            }
            out.append(']');
        } finally {
            serializer.setContext(context);
        }
    }
}

package com.controller;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@RestController
public class JsonController {
    
    @GetMapping("/testFastJson")
    public List