Javaマルチスレッドスレッド終了クリーンアップ
5439 ワード
この例では、クリーンアップ作業をfinallyブロックに配置する必要があることを示します.
package Thread.Interrupting;
import java.util.concurrent.TimeUnit;
class NeedsCleanup {
private final int id;
public NeedsCleanup(int ident) {
id = ident;
System.out.println("NeedsCleanup " + id);
}
public void cleanup() {
System.out.println("Cleaning up " + id);
}
}
class Blocked3 implements Runnable {
private volatile double d = 0.0;
@Override
public void run() {
try {
while (!Thread.interrupted()) {
NeedsCleanup n1 = new NeedsCleanup(1);
try {
System.out.println("Sleeping");
TimeUnit.SECONDS.sleep(1);
// point2
NeedsCleanup n2 = new NeedsCleanup(2);
// Guarantee proper cleanup of n2:
try {
System.out.println("Calculating");
// A time-consuming,non-blocking operation:
for (int i = 0; i < 2500000; i++) {
d = d + (Math.PI + Math.E) / d;
}
System.out.println("Finished time-consuming operation");
} finally {
n2.cleanup();
}
} finally {
n1.cleanup();
}
System.out.println("Exiting via while() test");
}
} catch (InterruptedException e) {
System.out.println("Exiting via InterruptedException");
}
}
}
public class InterruptingIdiom {
public static void main(String[] args) throws NumberFormatException,
InterruptedException {
if (args.length != 1) {
System.out.println("usage:java InterruptingIdiom delay-in-ms");
System.exit(1);
}
Thread t = new Thread(new Blocked3());
t.start();
TimeUnit.MILLISECONDS.sleep(new Integer(args[0]));
t.interrupt();
}
}