Programowanie współbieżne w języku Java

Prosty program zawierający dwa wątki (instrukcje niskopoziomowe), działanie mechanizmu
przerwao, wykorzystanie narzędzia Profiler z Netbeans IDE do obserwacji (Sun Java tutorial).
public class SimpleThreads {
public static long startTime = 0;
// Display a message, proceed by the name of current thread.
static void threadMessage (String message) {
String threadName = Thread.currentThread().getName();
long time = System.currentTimeMillis() - startTime;
System.out.format("%s: %d: %s%n", threadName, time, message);
}
private static class MessageLoop implements Runnable {
public void run() {
String importantInfo[] = {
"Message no.1", "Message no.2", "Message no.3", "Message no.4"
};
try {
for (int i = 0; i < importantInfo.length; i++) {
Thread.sleep(3500); // Pause for 3.5 seconds
threadMessage(importantInfo[i]);
}
} catch (InterruptedException e) {
threadMessage("I wasn't done!");
}
}
}
public static void main(String[] args) throws InterruptedException {
// delay in miliseconds before we interrupt MessageLoop thread
// default is one hour
long patience = 1000*60*60;
// If command line present gives patience in seconds
if (args.length > 0) {
try {
patience = Long.parseLong(args[0]) * 1000;
} catch (NumberFormatException e) {
System.err.println("Argument must be an integer.");
System.exit(1);
}
}
}
startTime = System.currentTimeMillis();
threadMessage("Starting MessageLoop thread - patience = "+
new Long(patience).toString());
Thread t = new Thread(new MessageLoop(),"myThread");
t.start();
threadMessage("Waiting for MessageLoop thread to finish.");
// loop until MessageLoop thread exits
while (t.isAlive()) {
threadMessage("Still waiting ...");
// wait maximum 1 second for MessageLoop thread to finish
t.join(1000);
if (((System.currentTimeMillis() - startTime) > patience) &&
t.isAlive()) {
threadMessage("Tired of waiting!");
t.interrupt();
t.join(); //Shouldn't be long now -- wait indefinetely
}
}
threadMessage("Finally - the end");
}
Lab. „Programowanie współbieżne w języku Java”
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