Thread

Thread?

プログラムカウンタ、レジスタグループ、スタックもスレッド単位である.(コード、データ、ファイルは共有されています.)

MutiThreadingの利点

サーバは、クライアントの要求処理をスレッドに渡して処理し、非ブロック方式(スレッド数)でクライアントの要求を受信し続ける.

Thread in Java

1.JavaでのThreadの使用

public class ThreadExample1{
    public static void main(String[] args) {
        // 1. Thread 클래스 상속
        MyThread1 myThread = new MyThread1();
        myThread.start();
        System.out.println("Hello, My Child!");

        // 2. Runnable 인터페이스 구현
        Thread thread = new Thread(new MyThread2());
        thread.start();
        System.out.println("Hello, My Runnable Child!");

        // 3. Lambda로 Runnable 인터페이스 구현
        Runnable task = () -> {
            try {
                while (true) {
                    System.out.println("Hello, Lambda Runnable!");
                    Thread.sleep(500);
                }
            } catch (InterruptedException ie) {
                System.out.println("I'm interrupted");
            }
        };
        System.out.println("Hello, My Lambda Child!");
    }
}

class MyThread1 extends Thread{
    public void run() {
        try {
            while (true) {
                System.out.println("Hello, Thread!");
                Thread.sleep(500);
            }
        } catch (InterruptedException ie) {
            System.out.println("I'm interrupted");
        }
    }
}

class MyThread2 implements Runnable {
    @Override
    public void run() {
        try {
            while (true) {
                System.out.println("Hello, Runnable!");
                Thread.sleep(500);
            }
        } catch (InterruptedException ie) {
            System.out.println("I'm interrupted");
        }
    }
}

OUTPUT(継承1.Threadクラス)

Hello, My Child!
Hello, Thread!
Hello, Thread!
Hello, Thread!
Hello, Thread!
Hello, Thread!
Hello, Thread!

2.親スレッド待ち:join

public class ThreadExample2 {
    public static void main(String[] args) {
        Runnable task = () -> {
            for (int i = 0; i < 5; i++) {
                System.out.println("Hello, Lambda Runnable!");
            }
        };

        Thread thread = new Thread(task);
        thread.start();
        try {
            thread.join(); // 이때 돌고 있는건 main
        } catch (InterruptedException ie) {
            System.out.println("Parent thread is interrupted");
        }
        System.out.println("Hello, My Joined Child!");
    }
}

OUTPUT

Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, My Joined Child!

3.スレッドのタイプ：interrupt

public class ThreadExample3 {
    public static void main(String[] args) throws InterruptedException {
        Runnable task = () -> {
            try {
                while (true) {
                    System.out.println("Hello, Lambda Runnable!");
                    Thread.sleep(100);
                }
            } catch (InterruptedException ie) {
                System.out.println("I'm interrupted");
            }
        };

        Thread thread = new Thread(task);
        thread.start();
        Thread.sleep(500);
        thread.interrupt();
        System.out.println("Hello, My Interrupted Child!");
    }
}

OUTPUT

Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
Hello, Lambda Runnable!
I'm interrupted
Hello, My Interrupted Child!

Multithreading in a Muiticore system

多目的注意事項

並列処理方法

Amdahl's Law