java Google HTTP库JSON解析，空值默认为True

Question

我正在使用Google HTTP库解析从get请求接收到的JSON数据，但现在发生的奇怪事情是，对于我的一个@key，JSON值为null（hashipmentbeenpulled）：

{
    "orderNo": 19.000,
    ...
    "customFields": {
        "hasShipmentBeenPulled": null,
        "service": null
    }
}

但当库解析出该值时，它默认为“true”。下面是课程：

public class CustomFields {
    @Key
    private Boolean hasShipmentBeenPulled;

    @Key
    private String service;

    public Boolean getHasShipmentBeenPulled() {
        return hasShipmentBeenPulled;
    }

    public void setHasShipmentBeenPulled(Boolean hasShipmentBeenPulled) {
        this.hasShipmentBeenPulled = hasShipmentBeenPulled;
    }

    public String getService() {
        return service;
    }

    public void setService(String service) {
        this.service = service;
    }
}

以下是输出：

OrderNo: 19 UseOrderNoRoot: 0 hasShipmentBeenPulled: true