fastjson2兼容包作为springboot默认序列化组件，无法默认序列化Date为时间戳

[feistel]

问题描述

简要描述您碰到的问题。
用的fastjson2 兼容包，针对Date类型，直接通过JSON.toJSONString就是默认序列化为时间戳的。

但是通过WebMvcConfigurer 替换springboot默认的jaskson序列化方式的时候，就不生效，直接序列化为yyyy-MM-dd HH:mm:ss 这种形式了
即便在FastJsonConfig设置dateformat= "millis" 也不会生效，请问这种问题该怎么解决呀

环境信息

请填写以下信息：

• JDK信息： 1.8.0
• 版本信息：fastjson 2.0.52

重现步骤

import java.nio.charset.StandardCharsets;
import java.util.List;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class MessageConverterWebMvcConfigurer implements WebMvcConfigurer {
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter();
        // 定义配置信息
        FastJsonConfig config = new FastJsonConfig();
        converter.setFastJsonConfig(config);
        converter.setDefaultCharset(StandardCharsets.UTF_8);
        converters.add(0, converter);
    }
}

期待的正确结果

默认序列化为时间错类型(millis)

[VictorZeng]

@feistel Can you provide a complete testcase?

[mek1986]

@VictorZeng
fastjson2的JSON.toJSONString，date序列为yyyy-MM-dd HH:mm:ss
fastjson1.x的JSON.toJSONString，date序列为mill
下面是测试代码和截图：

1. fastjson2的JSON

import com.alibaba.fastjson2.JSON;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;


@RequestMapping("/test")
@RestController
public class Issue2850 {
    static class TestData {
        public TestData() {
        }

        public TestData(Date showDate) {
            this.showDate = showDate;
        }

        private Date showDate;

        public Date getShowDate() {
            return showDate;
        }

        public void setShowDate(Date showDate) {
            this.showDate = showDate;
        }

        @Override
        public String toString() {
            return "TestData{" +
                    "showDate=" + showDate +
                    '}';
        }
    }

    @RequestMapping(path = "/issue2850/v1", produces = "application/json")
    public TestData issue2850V1() {
        return new TestData(new Date());
    }

    @RequestMapping(path = "/issue2850/v2", produces = "application/json")
    public String issue2850V2() {
        return JSON.toJSONString(new TestData(new Date()));
    }
}

2. fastjson1.的JSON

import com.alibaba.fastjson.JSON;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

/**
 * @author: mek
 * Date: 2024/8/10
 * Time: 15:15
 * vx: 250023777
 * Description: Issue 2850
 * @version: 1.0
 */
@RequestMapping("/test")
@RestController
public class Issue2850 {
    static class TestData {
        public TestData() {
        }

        public TestData(Date showDate) {
            this.showDate = showDate;
        }

        private Date showDate;

        public Date getShowDate() {
            return showDate;
        }

        public void setShowDate(Date showDate) {
            this.showDate = showDate;
        }

        @Override
        public String toString() {
            return "TestData{" +
                    "showDate=" + showDate +
                    '}';
        }
    }

    @RequestMapping(path = "/issue2850/v1", produces = "application/json")
    public TestData issue2850V1() {
        return new TestData(new Date());
    }

    @RequestMapping(path = "/issue2850/v2", produces = "application/json")
    public String issue2850V2() {
        return JSON.toJSONString(new TestData(new Date()));
    }
}

[mek1986]

@VictorZeng fastjson2的JSON.toJSONString，date序列为yyyy-MM-dd HH:mm:ss fastjson1.x的JSON.toJSONString，date序列为mill 下面是测试代码和截图：

1. fastjson2的JSON

import com.alibaba.fastjson2.JSON;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;


@RequestMapping("/test")
@RestController
public class Issue2850 {
    static class TestData {
        public TestData() {
        }

        public TestData(Date showDate) {
            this.showDate = showDate;
        }

        private Date showDate;

        public Date getShowDate() {
            return showDate;
        }

        public void setShowDate(Date showDate) {
            this.showDate = showDate;
        }

        @Override
        public String toString() {
            return "TestData{" +
                    "showDate=" + showDate +
                    '}';
        }
    }

    @RequestMapping(path = "/issue2850/v1", produces = "application/json")
    public TestData issue2850V1() {
        return new TestData(new Date());
    }

    @RequestMapping(path = "/issue2850/v2", produces = "application/json")
    public String issue2850V2() {
        return JSON.toJSONString(new TestData(new Date()));
    }
}

2. fastjson1.的JSON

import com.alibaba.fastjson.JSON;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

/**
 * @author: mek
 * Date: 2024/8/10
 * Time: 15:15
 * vx: 250023777
 * Description: Issue 2850
 * @version: 1.0
 */
@RequestMapping("/test")
@RestController
public class Issue2850 {
    static class TestData {
        public TestData() {
        }

        public TestData(Date showDate) {
            this.showDate = showDate;
        }

        private Date showDate;

        public Date getShowDate() {
            return showDate;
        }

        public void setShowDate(Date showDate) {
            this.showDate = showDate;
        }

        @Override
        public String toString() {
            return "TestData{" +
                    "showDate=" + showDate +
                    '}';
        }
    }

    @RequestMapping(path = "/issue2850/v1", produces = "application/json")
    public TestData issue2850V1() {
        return new TestData(new Date());
    }

    @RequestMapping(path = "/issue2850/v2", produces = "application/json")
    public String issue2850V2() {
        return JSON.toJSONString(new TestData(new Date()));
    }
}

fastjson配置就是用的提问者发的配置