fastjson2 [BUG] Boolean 字段private修饰使用valueFilter 会有问题

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<Integer>() { @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;
 }

} }