類Student代碼如下: class Student{ String name; int age; Student(String nm){ name = nm; } } 執(zhí)行語(yǔ)句Student stu = new Student()后,字段age的值是哪項(xiàng)?()
A. 0 B. null C. false D. 編譯錯(cuò)誤
A. 對(duì)象被創(chuàng)建后,立刻變成垃圾對(duì)象 B. 任何不再被引用的對(duì)象都是垃圾收集的對(duì)象 C. 一旦對(duì)象失去引用,垃圾收集器立刻把它從內(nèi)存中清除 D. Java對(duì)象的清除必須自己手動(dòng)處理
下述代碼執(zhí)行后,有幾個(gè)引用變量和幾個(gè)對(duì)象?() Student stu = new Student(“Mike”); Student stua; Stua = stu;
A. 2個(gè)引用變量,1個(gè)對(duì)象 B. 1個(gè)引用變量,1個(gè)對(duì)象 C. 2個(gè)引用變量,2個(gè)對(duì)象 D. 1個(gè)引用變量,2個(gè)對(duì)象