单项选择题 现有: class Bird { void talk() { System.out.print("chirp "); } } class Parrot2 extends Bird { protected void talk() { System.out.print("hello "); public static void main(String [] args) { Bird [] birds = {new Bird(), new Parrot2 () }; for( Bird b : birds) b.talk () ; } } 结果是什么 ?()
单项选择题 现有 class Beverage { Beverage () { System.out.print ("beverage "); } } class Beer extends Beverage { public static void main{string [] args) { Beer b = new Beer (14) ; } public int Beer(int x) { this () ; System.out.print ("beerl") ; } public Beer() { System.out.print("beer2 "); } } 结果是什么?()
单项选择题 现有: 1.class Over { 2.int dolt (long x) { return 3; } 3. } 4. 5. class Under extends Over { 6.//insert code here 7. } 和四个方法: short dolt (int y) { return 4; } int dolt(long Xr long y) { return 4; } private int dolt(short y) { return 4; } protected int dolt (long x) { return 4; } 分别插入到第6行,有几个可以通过编译?()