单项选择题
	A.b=nf.parse(input);
	B.b=nf.format(input);
	C.b=nf.equals(input);
	D.b=nf.parseObject(input);
单项选择题 Given a vaid DateFormat object named df, and What updates d’s value with the date represented by ds?()
多项选择题 Giventhatcisareferencetoavalidjava.io.Consoleobject,whichtwocodefragmentsreadalineoftextfromtheconsole?()
多项选择题 Whichthreestatementsconcerningtheuseofthejava.io.Serializableinterfacearetrue?()