[BUG] Boolean 字段private修饰使用valueFilter 会有问题

mystox commented 1 month ago

问题描述

实体中字段为Boolean时想将对应空值转成“”时报错，其中active 修饰为public的时候正常，请问这种情况是设计如此还是存在bug？补充一下似乎 Integer也有这个问题，自定义的ObjectWriter 不生效

@Data class User { public String name; public Integer age; private Boolean active;

public User(String name, Integer age, Boolean active) {
    this.name = name;
    this.age = age;
    this.active = active;
}

}

public class Fastjson2ValueFilterExample { public static void main(String[] args) { User user = new User("Alice", null, null);

    // 定义一个 ValueFilter，将 null 值修改为默认值
    ValueFilter filter = (object, name, value) -> {
        if (value == null) {
            return "N/A"; // 如果字段值为 null，改为 "N/A"
        }
        return value;
    };

    // 使用 ValueFilter 序列化
    String jsonString = JSON.toJSONString(user, filter, JSONWriter.Feature.WriteNulls);
    System.out.println(jsonString);
    // 输出：{"name":"Alice","age":"N/A","active":"N/A"}
}

}

提示报错 Exception in thread "main" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Boolean at com.alibaba.fastjson2.writer.ObjectWriterImplBoolean.write(ObjectWriterImplBoolean.java:25) at com.alibaba.fastjson2.writer.ObjectWriterAdapter.writeWithFilter(ObjectWriterAdapter.java:577) at com.alibaba.fastjson2.writer.ObjectWriter3.write(ObjectWriter3.java:63) at com.alibaba.fastjson2.JSON.toJSONString(JSON.java:3083) at com.itime.debtdefuse.assets.util.Fastjson2ValueFilterExample.main(Fastjson2ValueFilterExample.java:34)

似乎Integer字段也有这个问题

参考代码：

import com.alibaba.fastjson2.JSON; import com.alibaba.fastjson2.JSONWriter; import com.alibaba.fastjson2.writer.ObjectWriter;

import java.lang.reflect.Type; import java.math.BigDecimal; import java.util.HashMap; import java.util.Map;

/**

@author Baoyi Chen */ public class Main { public static void main(String[] args) { JSON.register(Integer.class, new ObjectWriter() { @Override public void write(JSONWriter jsonWriter, Object object, Object fieldName, Type fieldType, long features) { Integer value = (Integer) object; if (value == null) jsonWriter.writeNull(); else jsonWriter.writeString(Long.toString(value)); } });

JSON.register(BigDecimal.class, new ObjectWriter<BigDecimal>() {
    @Override
    public void write(JSONWriter jsonWriter, Object object, Object fieldName, Type fieldType, long features) {
        BigDecimal value = (BigDecimal) object;
        if (value == null) jsonWriter.writeNull(); else jsonWriter.writeString(value.toPlainString());
    }
});

Map<String, Long> map = new HashMap<>();
map.put("0", 0L);
String s = JSON.toJSONString(map);
System.out.println(s);

Test t = new Test();
t.setValue(0);
t.setValue1(new BigDecimal("0.11"));
s = JSON.toJSONString(t);
System.out.println(s);

}

public static class Test { private Integer value; private BigDecimal value1;

public Integer getValue() {
    return value;
}

public BigDecimal getValue1() {
    return value1;
}

public void setValue(Integer value) {
    this.value = value;
}

public void setValue1(BigDecimal value1) {
    this.value1 = value1;
}

} }

xcodemap commented 1 month ago

@mystox 看代码走向，跟非public类有关。推荐使用 XCodeMap 走读源码，追踪对象字段的生命周期，快速定位有效分支。 https://xcodemap.tech/

wenshao commented 2 weeks ago

https://oss.sonatype.org/content/repositories/snapshots/com/alibaba/fastjson/2.0.54-SNAPSHOT/ 问题已修复，请帮忙用2.0.54-SNAPSHOT快照版本验证，2.0.54正式版本预计在月底发布

mystox commented 2 weeks ago

https://oss.sonatype.org/content/repositories/snapshots/com/alibaba/fastjson/2.0.54-SNAPSHOT/ 问题已修复，请帮忙用2.0.54-SNAPSHOT快照版本验证，2.0.54正式版本预计在月底发布

验证符合期望，辛苦

alibaba / fastjson2