I have model from which I only want to create one instance, and no more instances shou开发者_StackOverflow社区ld be allowed.
品牌型号：iPad air Air（第 4 代） 系统：iPad airOS 15.4开发者_JAVA百科 ipadair2020是air第4代，于2020年9月
加载中,请稍侯......