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12. Java Threads: Defining and starting a thread

• Oracle: The Java Tutorials - Defining and Starting a Thread.
• Jenkov Aps: Creating and Starting Java Threads.

1) Make a new Eclipse project called task12.

2) Develop a program that prints a series of specified messages at specified intervals. Initial data: message text, delay, number of repetitions. Use the following class, add the required functionality.

class PrintMessageTask implements Runnable {
	private String text;
	private long delay;
	private int number;

	public PrintMessageTask(String text, long delay, int number) {
		this.text = text;
		this.delay = delay;
		this.number = number;
	}

	public void run() {
		// Add your implementation here.
		// ...
	}
}

3) Test the created class by measuring the time of printing messages:

PrintMessageTask task = new PrintMessageTask("abc", 1000, 5);
long startTime = System.currentTimeMillis();
task.run();
long elapsedMillis = System.currentTimeMillis() - startTime;
System.out.println("Time: " + elapsedMillis);

The result should look something like this:

abc
abc
abc
abc
abc
Time: 5002

4) Print a series of messages in separate threads. Use a new thread for each PrintMessageTask object.

5) Test multithreaded message printing for 20 or more different PrintMessageTask objects.

Hint: Use a random number generator to set parameters when creating objects.

6) Stop printing messages after the specified time has elapsed.

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