Monday 18 November 2019

Que Example

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.Queue;

public class QueueExmaple {

    public static void main(String[] args) {
        Queue<String> queue= new LinkedList<>();
        // Linked list implements que interface        queue.add("one");
        queue.add("two");

       System.out.println(queue.peek());// Returns head. if head is not present then returns null     
      System.out.println(queue.poll()); // Returns and Removes head
       System.out.println(queue.poll()); // Returns and Removes head 
       System.out.println(queue.peek()); // Returns head. if head is not present then returns null 
       System.out.println(queue.element()); // Returns head. 
    If head is not present then throws NoSuchElementException
    }
}

Sunday 10 November 2019

java 8 interface



two features added in java 8 interfaces

  1.  default methods
  2. Static methods
defaults methods


package com.vikas.blog.tut.interfacedemo;

public interface Inputs {

    public void calulateSum(double... inputs);

    default void printInputs(double... inputs ){
        for (double input:inputs
             ) {
            System.out.println(input);
        };
    }

}



package com.vikas.blog.tut.interfacedemo;

public class SumOfInputs implements Inputs {

    @Override    public void calulateSum(double... inputs) {

        System.out.println("Sum "+calulateSum(inputs,inputs.length-1));

    }

    public double calulateSum(double[] inputs, int index ) {

        if(index == 0)
          return inputs[0];

    return calulateSum(inputs,index-1) + inputs[index];


    }

    public static void main(String[] args) {
        double[] inputs= {3.0, 2.0,5.0};
        SumOfInputs conv= new SumOfInputs();
        conv.printInputs(inputs);
        conv.calulateSum(inputs);
    }
}