JSON.toJSONString()null值转“”

public static void main(String[] s) {
        CybWmsCommoditiesVo cybWmsCommoditiesVo = new CybWmsCommoditiesVo();
        CybItemVo cybItemVo = new CybItemVo();
        cybItemVo.setStockUnit("2134");
        cybWmsCommoditiesVo.setSupplierCode("24234");
        cybWmsCommoditiesVo.setItem(cybItemVo);
        
        String requestBody = JSON.toJSONString(cybWmsCommoditiesVo, filter);
        System.out.print(requestBody);
    }

private static ValueFilter filter = new ValueFilter() {
    @Override
    public Object process(Object obj, String s, Object v) {
        if (v == null)
            return "";
        return v;
    }
};

JSON.toJSONString()方法默认会将对象中的空字符串忽略.

加上这个过滤器后,所有的null值和""值都会被转换成""值输出到字符串中.

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private SerializerFeature[] features = new SerializerFeature[] {
        WriteMapNullValue, WriteNullNumberAsZero, WriteNullListAsEmpty,
        WriteNullStringAsEmpty,WriteDateUseDateFormat
};

return JSON.toJSONString(page, features);