您可以使用 JsonObject＃entrySet（） ，然后检查它的 size（）。

  JsonObject jsonObject = ...; 
 if（jsonObject.entrySet（）。size（）== 0）{//或isEmpty（）
 //做某事
} 
 

I used the Google Gson API to construct JSON. When I initialized a JsonObject with:

JsonObject json = new JsonObject();

and print it out, it was in fact {}.

I tried to exclude the "empty" JSON, i.e. the {} ones that were not added any properties. But I could not find a method resembling isEmpty() in the Gson API.

How can I find out the "empty" JSON with Gson API?

You can use JsonObject#entrySet() then check its size().

JsonObject jsonObject = ...;
if (jsonObject.entrySet().size() == 0) { // or isEmpty()
    // do something
}