class Beta { public static void main(String [] args) { Integer x = new Integer(6) * 7; if (x != 42) { System.out.print("42 "); } else if (x.equals(42)) { System.out.print("dot = "); } else { System.out.print("done"); } } } 结果为:()
public class Pet{} public class Cat extends Pet{} 执行代码 Cat c = new Cat(); Pet p = (Pet)c; 下列哪项是正确的?
Random early detection (RED) is associated with which class of service component?()
Which statement is true for the class java.util.HashSet? ()
Given that Thing is a class, how many objects and reference variables are created by the following code?() Thing item, stuff; item = new Thing(); Thing entity = new Thing();
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){ this(); System.out.print(3); } } 执行new Dog(“棕熊”);后程序输出是哪项?()
class A { A() { } } class B extends A { } Which two statements are true?()
public class Parent{ public void change(int x){} } public class Child extends Parent{ //覆盖父类change方法 } 下列哪个声明是正确的覆盖了父类的change方法?()
1. abstract class Color2 { 2. //insert code here 3. } 4. 5. public class Blue2 extends Color2 { 6. public String getRGB() { return "blue"; } 7. } 和4个声明: public abstract String getRGB(); abstract String getRGB(); private abstract String getRGB(); protected abstract String getRGB(); 分别插入到第2行,有多少行可以编译?()
A fire in a pile of linen is considered to be a class ().