class TestMain { static int x = 2; static { x = 4; } static public void main(String[] args) { int y = x + 1; System.out.println(y); } } 和命令行: java TestMain 結(jié)果為:()
A. 3 B. 5 C. 編譯失敗 D. 運(yùn)行時(shí)異常被拋出
public class Employee{ private String name; public Employee(String name){ this.name = name; } public void display(){ System.out.print(name); } } public class Manager extends Employee{ private String department; public Manager(String name,String department){ super(name); this.department = department; } public void display(){ System.out.println( super.display()+”,”+department); } } 執(zhí)行語(yǔ)句new Manager(“smith”,”SALES”)后程序的輸出是哪項(xiàng)?()
A. smith,SALES B. null,SALES C. smith,null D. null,null
public class Pet{ private String name; public Pet(){ System.out.print(1); } public Pet(String name){ System.out.print(2); } } public class Dog extends Pet{ public Dog(){ System.out.print(4); } public Dog(String name){ super(name); System.out.print(3); } } 執(zhí)行new Dog(“棕熊”);后程序輸出是哪項(xiàng)?()
A. 33 B. 13 C. 23 D. 123