Question

JAVA:

You're given 3 files. Demo.java, SampleInterace.java, and OverflowException.java. Use your Demo class to implement SampleInterface, and the OverflowException class should handle any errors that may come from the addNum method.

Demo.java:

public class Demo implements SampleInterface {

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated constructor stub

}

@Override

public void addNum(int value) throws OverflowException {

// TODO Auto-generated method stub

}

@Override

public void removeNum(int value) {

// TODO Auto-generated method stub

}

@Override

public int sumOfNumbers() {

// TODO Auto-generated method stub

return 0;

}

@Override

public void clear() {

// TODO Auto-generated method stub

}

@Override

public boolean isFull() {

// TODO Auto-generated method stub

return false;

}

@Override

public boolean isEmpty() {

// TODO Auto-generated method stub

return false;

}

}

SampleInterface.java :

public interface SampleInterface {

/**

* Method adds a value to the list if the list doesn't have the value already

* If your list is full then the

* is full this method throws a OverflowException.

*

* @throws OverflowException

*/

public void addNum(int value) throws OverflowException;

/**

* This method will remove a value in your list if it's present

* If the value does not exist in this list then the list should remain unchanged

*

*/

public void removeNum(int value);

/**

* Method should add all numbers currently stored in the list and return it

* @return the sum of all the numbers stored in this object.

*/

public int sumOfNumbers();

/**

* removes all numbers from this object.

*/

public void clear();

/**

* Checks if the current list is full or not.

* @return true if the list in this object is full. false otherwise.

*/

public boolean isFull();

/**

* Checks if the current list is empty or not.

* @return true if the list in this object is empty. false otherwise.

*/

public boolean isEmpty();

}

OverflowException.java :

public class OverflowException extends Exception {

/**

*

*/

public OverflowException() {

// TODO Auto-generated constructor stub

}

/**

* @param arg0

*/

public OverflowException(String arg0) {

super(arg0);

// TODO Auto-generated constructor stub

}

/**

* @param arg0

*/

public OverflowException(Throwable arg0) {

super(arg0);

// TODO Auto-generated constructor stub

}

/**

* @param arg0

* @param arg1

*/

public OverflowException(String arg0, Throwable arg1) {

super(arg0, arg1);

// TODO Auto-generated constructor stub

}

/**

* @param arg0

* @param arg1

* @param arg2

* @param arg3

*/

public OverflowException(String arg0, Throwable arg1, boolean arg2, boolean arg3) {

super(arg0, arg1, arg2, arg3);

// TODO Auto-generated constructor stub

}

}

Answer 1

Short Summary:

• Implemented the Demo class as per the requirement
• Attached source code and output

Source Code:

Demo.java

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Demo implements SampleInterface {

   static List<Integer> list = new ArrayList<Integer> (Arrays.asList(new Integer[5]));
   int index;

   /**

   * @param args
   * @throws OverflowException

   */

   public static void main(String[] args) throws OverflowException {

       //Test the methods
       Demo obj=new Demo();
       System.out.println("******Test addNum method******");
       obj.addNum(5);
       obj.addNum(6);
       obj.addNum(7);
       obj.addNum(8);
       obj.addNum(9);
       obj.addNum(6);
       //Uncomment the below line to test Overflow exception
       //   obj.addNum(10);
       System.out.println(list);
       System.out.println("******Test removeNum method - Remove 5 from list******");
       obj.removeNum(5);
       System.out.println(list);
       System.out.println("******Test isEmpty method******");
       System.out.println(obj.isEmpty());
       System.out.println(list);
       System.out.println("******Test isFull method******");
       System.out.println(obj.isFull());
       System.out.println("******Test sumOfNumbers method******");
       System.out.println(obj.sumOfNumbers());
       System.out.println("******Test clear method******");
       obj.clear();
       System.out.println(list);

   }

   /**

   * Method adds a value to the list if the list doesn't have the value already

   * If your list is full then the

   * is full this method throws a OverflowException.

   *

   * @throws OverflowException

   */
   @Override

   public void addNum(int value) throws OverflowException {

       try
       {
           if(!list.contains(value))
           {
               //list.add(value);

               list.set(index, value);
               index++;
           }
       }
       catch(Exception ex)
       {
           throw new OverflowException(ex.getLocalizedMessage());
       }

   }
   /**

   * This method will remove a value in your list if it's present

   * If the value does not exist in this list then the list should remain unchanged

   *

   */
   @Override

   public void removeNum(int value) {

       for(int i=0;i<list.size();i++)
       {
           if(list.get(i)==value)
           {
               list.remove(i);
               index--;
           }
       }
   }

   /**

   * Method should add all numbers currently stored in the list and return it

   * @return the sum of all the numbers stored in this object.

   */
   @Override

   public int sumOfNumbers() {

       int sum=0;
       for(int i=0;i<list.size();i++)
       {
           sum=sum+list.get(i);
       }

       return sum;

   }

   /**

   * removes all numbers from this object.

   */
   @Override

   public void clear() {

       list.clear();

   }

   /**

   * Checks if the current list is full or not.

   * @return true if the list in this object is full. false otherwise.

   */
   @Override

   public boolean isFull() {

       try
       {
           list.set(index,1);
       }
       catch(Exception ex)
       {
           return true;
       }
       return false;

   }

   /**

   * Checks if the current list is empty or not.

   * @return true if the list in this object is empty. false otherwise.

   */
   @Override

   public boolean isEmpty() {

       if(list.isEmpty())
           return true;

       return false;

   }

}

Code Screenshot:

Output: (Uncomment line no 32 to test Overflow Exception)

**************Please do upvote to appreciate our time. Thank you!******************