I can not get Validators

[LuffySmile]

when I use ValidatorsApi to get the validators, I get null. My code is :
Validators validators = ValidatorsApi.getValidators(); System.out.println(validators.getValidators().get(0).getPower());

[LuffySmile]

I have solved this problem。
go into Validator.java, then change @SerializedName("pub_key") to @SerializedName("public_key") and @SerializedName("power") to @SerializedName("voting_power");
go into ValidatorPubKey.java ,then change @SerializedName("data") to @SerializedName("value")