Generic functions - odd count, maximum value in range, exchange elements

/*

Write java programs that include generic method to satisfy the following property.

To counts the number of odd integers in an integer list

To exchange the positions of two different elements in an array.

To find the maximal element in the range [begin, end] of a list.

*/

// Generic programming

import java.util.*;

class Gen<T1 extends Number>

{

     int max;

     T1 [] Arr;

     Scanner s = new Scanner(System.in);

    

     Gen(T1 [] A)

     {

          Arr = A;

     }

    

     public void fnOdd()

     {

          int oddcount = 0;

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

          {

              int x = (int)(Arr[i].doubleValue());

             

              if(x%2==1)

                   oddcount++;   

          }

          System.out.println("Number of odd elements = "+oddcount);

     }

    

     public void fnExchange()

     {

          System.out.print("\nEnter position 1 : ");

          int pos1 = s.nextInt();

         

          System.out.print("\nEnter position 2 : ");

          int pos2 = s.nextInt();

         

          if(pos1<Arr.length && pos2<Arr.length)

          {

              System.out.println("Array elements before exchange : ");

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

              System.out.print(Arr[i]+"\t");

             

              T1 tmp = Arr[pos1];

              Arr[pos1] = Arr[pos2];

              Arr[pos2] = tmp;

             

              System.out.println("\nArray elements after exchange : ");

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

              System.out.print(Arr[i]+"\t");

          }

          else

              System.out.println("Invalid positions.");

     }

    

     public void fnMax()

     {

          System.out.print("\nEnter starting position : ");

          int pos1 = s.nextInt();

          System.out.print("\nEnter ending position : ");

          int pos2 = s.nextInt();

         

          if(pos1<Arr.length && pos2<Arr.length && pos1<pos2)

          {

              max = (int)Arr[pos1].doubleValue();

              for(int i = pos1+1;i<pos2;i++)

                   if((int)Arr[i].doubleValue() > max )

                        max = (int)Arr[i].doubleValue();

                  

              System.out.println("\nMaximum element = "+max);

          }

          else

              System.out.println("Invalid positions.");   

     }

}

public class GP1

{

     public static void main(String as[])

     {

          Integer [] IntArr = {2,4,1,6,5,3,7};

         

          Gen<Integer> g1 = new Gen<Integer>(IntArr);

          g1.fnOdd();

          g1.fnExchange();

          g1.fnMax();

         

     }

}