这个程序不符合我的要求。它打印了两次“sad”，而我希望它会打印“happy”然后打印“sad”。publicclassWoof{publicstaticclassArf{Tyap;publicArf(Tyap){this.yap=yap;}publicStringwoof(){/**ShouldselectwhichdoYapStuff()basedonwhetherT*happenstobeanInteger,orsomethingelse.*/returndoYapStuff(yap);}/*SpecialcaseimplementationofdoYapStuff()where