Java'da Timer ve TimerTask Sınıflarının Kullanımı

package com.asosyalbebe.timers;

import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

public class MyFirstTimerApplication {
    public static void main(String[] args) {
        // Create 2 timers
        // which means 2 threads
        Timer timer1 = new Timer("MyTimer-1");
        Timer timer2 = new Timer("MyTimer-2");

        System.out.println("Scheduling tasks...");
        // Schedule the first task on the first timer
        timer1.scheduleAtFixedRate(new SimpleTimerTask("Task1"), 0, 50);
        // Schedule the second task on the second timer
        timer2.scheduleAtFixedRate(new SimpleTimerTask("Task2"), 0, 100);
        // Schedule the third task on the second timer
        timer2.scheduleAtFixedRate(new SimpleTimerTask("Task3"), 5, 100);

        try {
            // Sleep main thread for 500 ms
            // Timer threads continue executing
            Thread.sleep(500);
        } catch (InterruptedException e) {
            System.out.println("Interrupted! Exiting...");
            System.exit(0);
        }

        // Here, main thread woke up
        System.out.println("Main thread woke up!");
        // Cancel all timers
        timer1.cancel();
        timer2.cancel();
        System.out.println("Timers were cancelled!");
    }

    public static class SimpleTimerTask extends TimerTask {
        private String name;

        public SimpleTimerTask(String name) {
            this.name = name;
        }

        @Override
        public void run() {
            String dateStr = String.valueOf(new Date().getTime());
            String currentThreadStr = Thread.currentThread().getName();
            System.out.printf("SimpleTimerTask {name: %s, date: %s, thread: %s}\n", name, dateStr, currentThreadStr);
        }
    }
}

package com.asosyalbebe.timers;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Timer;
import java.util.TimerTask;

public class TimerWithLatency {
    public static void main(String[] args) {
        Timer timer = new Timer();
        timer.scheduleAtFixedRate(new LongTimerTask(), 0, 100);

        try {
            System.out.println("Main thread is sleeping.");
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            System.out.println("Oh no! I'm interrupted!");
            System.exit(0);
        }

        System.out.println("Main thread woke up!");
        timer.cancel();
        System.out.println("Timer cancelled!");
    }

    public static class LongTimerTask extends TimerTask {
        @Override
        public void run() {
            // This is a long task
            long startDate = System.currentTimeMillis();
            System.out.println("TaskStarted = " + startDate);
            try {
                File file = new File("test-file.txt");
                for (int i = 0; i < 5000; i++) {
                    FileWriter fileWriter = new FileWriter(file);
                    fileWriter.append("Line" + i + "n");
                    fileWriter.flush();
                    fileWriter.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            long finishDate = System.currentTimeMillis();

            System.out.println("TimePassed = " + (finishDate - startDate));
        }
    }
}

package com.asosyalbebe.timers;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.lang.reflect.InvocationTargetException;
import java.util.Timer;
import java.util.TimerTask;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class TimerForGirlfriend extends JFrame {
    private static final long serialVersionUID = 1L;
    private static final String MESSAGE = "I love you ${GIRLFRIEND_NAME}";

    private CustomJPanel panel;
    private JLabel label;

    public TimerForGirlfriend() {
        super(MESSAGE);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        panel = new CustomJPanel();
        label = new JLabel();
        label.setFont(new Font("Comic Sans MS", Font.BOLD, 25));
        label.setForeground(Color.BLUE);
        panel.add(label);

        setContentPane(panel);
        setSize(new Dimension(500, 100));
        setResizable(false);
        setLocationRelativeTo(null);
    }

    public JLabel getLabel() {
        return label;
    }

    private static class CustomJPanel extends JPanel {
        private static final long serialVersionUID = 1L;

        @Override
        protected void paintComponent(Graphics g) {
            g.setColor(Color.WHITE);
            g.fillRect(0, 0, getWidth(), getHeight());
        }
    }

    private static class WriteTimerTask extends TimerTask {
        private JLabel label;
        private int charIndex = 0;
        private String message = "";

        public WriteTimerTask(JLabel label) {
            this.label = label;
        }

        @Override
        public void run() {
            if (charIndex == MESSAGE.length()) {
                // Whole message was displayed.
                return;
            }
            message += MESSAGE.charAt(charIndex++);

            SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    // Do UI update in event dispatcher thread
                    label.setText(message);
                }
            });
        }
    }

    private static class BlinkTimerTask extends TimerTask {
        private JLabel label;
        private int colorIndex = 0;
        private Color[] colors = new Color[] {
            Color.BLACK, Color.BLUE, Color.RED, Color.YELLOW, Color.MAGENTA, Color.GREEN
        };

        public BlinkTimerTask(JLabel label) {
            this.label = label;
        }

        @Override
        public void run() {
            final Color color = colors[colorIndex % colors.length];
            colorIndex++;

            SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    // Do UI update in event dispatcher thread
                    label.setForeground(color);
                }
            });
        }
    }

    public static void main(String[] args) throws InterruptedException, InvocationTargetException {
        final TimerForGirlfriend frame = new TimerForGirlfriend();

        SwingUtilities.invokeAndWait(new Runnable() {
            @Override
            public void run() {
                // UI code must run in event dispatcher thread
                frame.setVisible(true);
            }
        });

        // Run after the frame is visible
        Timer timer = new Timer();
        int writeTimerTaskEndTime = 200 * (MESSAGE.length() + 2);
        timer.scheduleAtFixedRate(new WriteTimerTask(frame.getLabel()), 200, 200);
        timer.scheduleAtFixedRate(new BlinkTimerTask(frame.getLabel()), writeTimerTaskEndTime, 200);
    }
}