Question

Consider the Top class i public abstract class Topí 2 private 3 protected String name; 4 public intx - 12; int age; e public Top(String name)[ this.namename age0; System.out.println(x); 10 12 public abstract void foo(String f); 13 Create a Middle class that extends the Top class. The class should have a single constructor that takes two input parameters: a String (for name) and int (for age). Your constructor should not have any redundant code (i.e., code that is repeated elsewhere). The foo method of Middle should print (to standard output) the object's name and age. The foo method should not be able to be modified by a child class of Middle. Each Middle object also has an Integer attribute called middle that should be assigned to 42 when an object is created The Middle class should have an abstract method called bar that take no input parameters and returns void
All question base on Java Se 8

Answer 1

B.

// Top.java

public abstract class Top {

      

       private int x=12;

       protected String name;

       public int age;

      

       public Top(String name)

       {

             this.name = name;

             age=0;

             System.out.println(x);

       }

      

       public abstract void foo(String f);

}

//end of Top.java

// Middle.java

public abstract class Middle extends Top{

      

       private int middle ;

      

       //constructor

       public Middle(String name, int age)

       {

             super(name); // calling Top constructor

             middle=42;

             this.age=age;

       }

      

       public final void foo(String f) // the method is final hence it cannot be modified by a child class of Middle

       {

             System.out.println("Name : "+name+" Age : "+age);

       }

       public abstract void bar(); // abstract method

}

//end of Middle.java

C.

//Box.java

public class Box implements Comparable<Box>{

      

       public String a;

       protected String b;

      

       public Box(String a, String b)

       {

             this.a = a;

             this.b = b;

       }

       @Override

       public final int compareTo(Box b2) {

             if(a.compareTo(b2.a) < 0)

                    return -1;

             else if(a.equals(b2.a) && ((a.length()+b.length()) < (b2.a.length()+b2.b.length())))

                    return -1;

             else if(a.equals(b2.a) && ((a.length()+b.length()) == (b2.a.length()+b2.b.length())))

                    return 0;

             else

                    return 1;

       }

}

//end of Box.java

D.

// Program.java

import java.util.Arrays;

public class Program {

       public static String letters[]= {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};

       public static String LETTERS[]= {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};

      

       public static Box[] vowelBox(Box boxes[])

       {

             Box vowels[] = new Box[0];

             for(int i=0;i<boxes.length;i++)

             {

                    if(boxes[i].compareTo(new Box("a","A")) == 0 || boxes[i].compareTo(new Box("e","E"))==0 || boxes[i].compareTo(new Box("i","I")) == 0

                                 || boxes[i].compareTo(new Box("o","O")) == 0 || boxes[i].compareTo(new Box("u","U")) == 0)

                    {

                          

                           vowels = Arrays.copyOf(vowels, vowels.length+1);

                           vowels[vowels.length-1] = boxes[i];

                    }

             }

             return vowels;

       }

      

       public static void main(String[] args) {

             if(args.length < 2)

             {

                    System.out.println("Insufficient arguments");

                    System.exit(0);

                   

             }

             int start = Integer.parseInt(args[0]);

             int stop = Integer.parseInt(args[1]);

            

             Box boxes[] = new Box[stop-start+1];

             System.out.println(" Boxes created : ");

             for(int i=start;i<=stop;i++)

             {

                    boxes[i-start]= new Box(letters[i-1],LETTERS[i-1]);

                    System.out.println(" a = "+boxes[i-start].a+" b = "+boxes[i-start].b);

             }

             System.out.println("Vowel Boxes : ");

             Box vowels[] = vowelBox(boxes);

            

             for(int i=0;i<vowels.length;i++)

                    System.out.println(" a = "+vowels[i].a+" b = "+vowels[i].b);

       }

}

//end of Program.java

Output:

null