1 @Bean注解创建ObjectMapper实现

1.1 JsonConfig

全局序列化配置类。

package com.config;

import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

import java.text.SimpleDateFormat;

/**
 * 全局序列化配置类
 */
@Configuration
public class JsonConfig {

    /**
     * 创建Jackson对象映射器
     *
     * @param builder Jackson对象映射器构建器
     * @return
     */
    @Bean
    public ObjectMapper getJacksonObjectMapper(Jackson2ObjectMapperBuilder builder) {
        ObjectMapper objectMapper = builder.createXmlMapper(false).build();
        //序列换成json时,将所有的long变成string.因为js中得数字类型不能包含所有的java long值，超过16位后会出现精度丢失
        SimpleModule simpleModule = new SimpleModule();
        simpleModule.addSerializer(Long.class, com.fasterxml.jackson.databind.ser.std.ToStringSerializer.instance);
        simpleModule.addSerializer(Long.TYPE, com.fasterxml.jackson.databind.ser.std.ToStringSerializer.instance);
        objectMapper.registerModule(simpleModule);
        //反序列化的时候如果多了其他属性,不抛出异常
        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        //日期格式处理
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
        return objectMapper;
    }
}

1.2 调试代码

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 {
    /**
     * 测试使用@Bean注解方式实现全局序列化配置
     *
     * @return
     */
    @GetMapping("/testJacksonByBean")
    public List<Object> testJacksonByBean() {
        List<Object> list = new ArrayList<>();
        list.add(1440931124753108994L);
        list.add(new Date());
        return list;
    }
}

1.3 调试结果

 2 重写configureMessageConverters方法实现

2.1 JsonConfig

全局序列化配置类。

package com.config;

import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.List;

/**
 * 全局序列化配置类
 */
@Configuration
@EnableWebMvc
public class JsonConfig implements WebMvcConfigurer {

    /**
     * 全局序列化方式
     *
     * @param converters
     */
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        //Jackson的全局序列化方式
        configureJacksonHttpMessageConverter(converters);
    }

    /**
     * Jackson的全局序列化方式
     *
     * @param converters
     */
    private void configureJacksonHttpMessageConverter(List<HttpMessageConverter<?>> converters) {
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        ObjectMapper objectMapper = new ObjectMapper();
        //序列换成json时,将所有的long变成string.因为js中得数字类型不能包含所有的java long值，超过16位后会出现精度丢失
        SimpleModule simpleModule = new SimpleModule();
        simpleModule.addSerializer(Long.class, com.fasterxml.jackson.databind.ser.std.ToStringSerializer.instance);
        simpleModule.addSerializer(Long.TYPE, com.fasterxml.jackson.databind.ser.std.ToStringSerializer.instance);
        objectMapper.registerModule(simpleModule);
        //反序列化的时候如果多了其他属性,不抛出异常
        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        //日期格式处理
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
        converter.setObjectMapper(objectMapper);
        converters.add(converter);
        converters.add(new StringHttpMessageConverter(StandardCharsets.UTF_8));
    }
}

 2.2 调试代码

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 {

    /**
     * 测试重写configureMessageConverters方法实现全局序列化配置
     *
     * @return
     */
    @GetMapping("/testJacksonByAddOverrideMethod")
    public List<Object> testJacksonByAddOverrideMethod() {
        List<Object> list = new ArrayList<>();
        list.add(1440931124753108994L);
        list.add(new Date());
        return list;
    }
}

2.3 调试结果