¿Cómo crear hilos usando expresiones Lambda en Java?

Las expresiones Lambda se introducen en Java SE8. Estas expresiones están desarrolladas para interfaces funcionales . Una interfaz funcional es una interfaz con un solo método abstracto. Para saber más sobre las Expresiones Lambda haga clic aquí .

Sintaxis:

(argumento1, argumento2, .. argumento n) -> {

// declaraciones

};

Aquí hacemos uso de la interfaz ejecutable . Como es una interfaz funcional , se pueden usar expresiones lambda. Los siguientes pasos se realizan para lograr la tarea:

• Cree la referencia de la interfaz Runnable y escriba la expresión Lambda para el método run().
• Cree un objeto de clase Thread pasando la referencia creada anteriormente de la interfaz Runnable ya que el método start() está definido en la clase Thread, su objeto necesita ser creado.
• Invoque el método start() para ejecutar el hilo.

Ejemplos

Ejemplo 1:

public class Test {
 
    public static void main(String[] args)
    {
 
        // Creating Lambda expression for run() method in
        // functional interface "Runnable"
        Runnable myThread = () ->
        {
 
            // Used to set custom name to the current thread
            Thread.currentThread().setName("myThread");
            System.out.println(
                Thread.currentThread().getName()
                + " is running");
        };
 
        // Instantiating Thread class by passing Runnable
        // reference to Thread constructor
        Thread run = new Thread(myThread);
 
        // Starting the thread
        run.start();
    }
}

myThread is running

Ejemplo 2: 

Multithreading-1 usando expresiones lambda

public class Test {
 
    public static void main(String[] args)
    {
        Runnable basic = () ->
        {
 
            String threadName
                = Thread.currentThread().getName();
            System.out.println("Running common task by "
                               + threadName);
        };
 
        // Instantiating two thread classes
        Thread thread1 = new Thread(basic);
        Thread thread2 = new Thread(basic);
 
        // Running two threads for the same task
        thread1.start();
        thread2.start();
    }
}

Running common task by Thread-1
Running common task by Thread-0

Ejemplo 3: 

Multithreading-2 usando expresiones lambda

import java.util.Random;
 
// This is a random player class with two functionalities
// playGames and playMusic
class RandomPlayer {
 
    public void playGame(String gameName)
        throws InterruptedException
    {
 
        System.out.println(gameName + " game started");
 
        // Assuming game is being played for 500
        // milliseconds
        Thread.sleep(500); // this statement may throw
                           // interrupted exception, so
                           // throws declaration is added
 
        System.out.println(gameName + " game ended");
    }
 
    public void playMusic(String trackName)
        throws InterruptedException
    {
 
        System.out.println(trackName + " track started");
 
        // Assuming music is being played for 500
        // milliseconds
        Thread.sleep(500); // this statement may throw
                           // interrupted exception, so
                           // throws declaration is added
 
        System.out.println(trackName + " track ended");
    }
}
 
public class Test {
 
    // games and tracks arrays which are being used for
    // picking random items
    static String[] games
        = { "COD",      "Prince Of Persia", "GTA-V5",
            "Valorant", "FIFA 22",          "Fortnite" };
    static String[] tracks
        = { "Believer", "Cradles", "Taki Taki", "Sorry",
            "Let Me Love You" };
 
    public static void main(String[] args)
    {
 
        RandomPlayer player
            = new RandomPlayer(); // Instance of
                                  // RandomPlayer to access
                                  // its functionalities
 
        // Random class for choosing random items from above
        // arrays
        Random random = new Random();
 
        // Creating two lambda expressions for runnable
        // interfaces
        Runnable gameRunner = () ->
        {
 
            try {
 
                player.playGame(games[random.nextInt(
                    games.length)]); // Choosing game track
                                     // for playing
            }
            catch (InterruptedException e) {
 
                e.getMessage();
            }
        };
 
        Runnable musicPlayer = () ->
        {
 
            try {
 
                player.playMusic(tracks[random.nextInt(
                    tracks.length)]); // Choosing random
                                      // music track for
                                      // playing
            }
            catch (InterruptedException e) {
 
                e.getMessage();
            }
        };
 
        // Instantiating two thread classes with runnable
        // references
        Thread game = new Thread(gameRunner);
        Thread music = new Thread(musicPlayer);
 
        // Starting two different threads
        game.start();
        music.start();
 
        /*
         *Note: As we are dealing with threads output may
         *differ every single time we run the program
         */
    }
}

Believer track started
GTA-V5 game started
Believer track ended
GTA-V5 game ended