method swap to the Pair class of that swaps the first and second elements value of the pair in generic Pair class in java code example

Example 1: method swap to the Pair class of that swaps the first and second elements value of the pair in generic Pair class in java

public Pair<U,T> swap() {
  return new Pair(second, first);
}

Example 2: method swap to the Pair class of that swaps the first and second elements value of the pair in generic Pair class in java

public class PairDemo
{
   public static void main(String[] args)
   {
      String[] names = { "Tom", "Diana", "Harry" };
      Pair<String, Integer> result = firstContaining(names, "a");
      System.out.println(result.getFirst());
      System.out.println("Expected: Diana");
      System.out.println(result.getSecond());
      System.out.println("Expected: 1");
      swap();
   }


   public static Pair<String, Integer> firstContaining(
      String[] strings, String sub)
   {
      for (int i = 0; i < strings.length; i++)
      {
         if (strings[i].contains(sub))
         {
            return new Pair<String, Integer>(strings[i], i);
         }
      }
      return new Pair<String, Integer>(null, -1);
   }
}

Example 3: method swap to the Pair class of that swaps the first and second elements value of the pair in generic Pair class in java

public class Pair<T>
    {
       private T first;
       private T second;



   public Pair(T firstElement, T secondElement)
   {
      first = firstElement;
      second = secondElement;
   }


   public T getFirst() { return first; }

   public T getSecond() { return second; }

  public void swap()
  {

   T temp = first;
    first = second;
    second = temp;
  }

   public String toString() { return "(" + first + ", " + second + ")"; }
}