kunals201

public class IfPresentExample {
    
    public static void main(String[] args) {
        
        List<Integer> numbers = Arrays.asList(10, 20, 30, 40, 50, 60, 70, 80, 90);
    
    
                Optional<Integer> first =  numbers.stream().filter(a -> a > 500).findFirst();
        
                

kunals201

public class IfPresentOrElseExample {
    
    public static void main(String[] args) {
        
        List<Integer> numbers = Arrays.asList(10, 20, 30, 40, 50, 60, 70, 80, 90);
        
        Optional<Integer> first = numbers.stream().filter(a -> a > 500).findFirst();
        
        if (first.isPresent()) {
            System.out.println(first.get());

kunals201

package pack1;

public class Demo1
{
  public void test()
  {
     System.out.println("pack1.test");
  } 
}

kunals201

package pack2;
import pack1.Demo1;

public class Demo2 {
  public void test2()
  {
    System.out.println("pack2.Demo2 method");
    Demo1 obj = new Demo1();
    obj.test();
  }

kunals201

import pack2.Demo2;

class Test {
    public static void main(String[] args) {
        System.out.println("Test class main");
        Demo2 obj = new Demo2();
        obj.test2();
    }
}

kunals201

case class User(id: Int, name: String)

case class Tweet(id: Int, content: String)

object Test extends App{
  
  val user = User(1, "Kunal")
  val tweet = Tweet(11, "Scala Rocks")

  println(s"User ID :- ${user.id}")

kunals201

case class UserId(id: Int)

case class Username(name: String)

case class TweetId(id: Int)

case class TweetContent(content: String)

case class User(id: UserId, name: Username)

kunals201

case class UserId(id: Int) extends AnyVal

case class Username(name: String) extends AnyVal

case class TweetId(id: Int) extends AnyVal

case class TweetContent(content: String) extends AnyVal

case class User(id: UserId, name: Username)

kunals201

package com.knoldus;

import java.util.ArrayList;
import java.util.stream.Collectors;

public class LambdaEx {

    public static void main(String[] args) {
        ArrayList<String> list1 = null;
        list1.stream().map(elem -> elem + "Knoldus").collect(Collectors.toList());

kunals201

package com.knoldus;

import org.apache.commons.collections4.CollectionUtils;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class LambdaEx {