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Show all versions of org.apache.servicemix.bundles.dnsjava
Show all versions of org.apache.servicemix.bundles.dnsjava
This OSGi bundle wraps ${pkgArtifactId} ${pkgVersion} jar file.
// SPDX-License-Identifier: BSD-3-Clause
package org.xbill.DNS;
import java.time.Duration;
import java.util.ArrayDeque;
import java.util.Queue;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionStage;
import java.util.concurrent.TimeUnit;
import lombok.extern.slf4j.Slf4j;
@Slf4j
final class AsyncSemaphore {
private final Queue> queue = new ArrayDeque<>();
private final Permit singletonPermit = new Permit();
private volatile int permits;
final class Permit {
public void release() {
synchronized (queue) {
CompletableFuture next = queue.poll();
if (next == null) {
permits++;
} else {
next.complete(this);
}
}
}
}
AsyncSemaphore(int permits) {
this.permits = permits;
}
CompletionStage acquire(Duration timeout) {
synchronized (queue) {
if (permits > 0) {
permits--;
return CompletableFuture.completedFuture(singletonPermit);
} else {
TimeoutCompletableFuture f = new TimeoutCompletableFuture<>();
f.compatTimeout(timeout.toNanos(), TimeUnit.NANOSECONDS)
.whenComplete((result, ex) -> queue.remove(f));
queue.add(f);
return f;
}
}
}
}
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