*
   * Lock lockA = factory1.newReentrantLock(MyLockOrder.FIRST);
   * Lock lockB = factory1.newReentrantLock(MyLockOrder.FIRST);
   * Lock lockC = factory2.newReentrantLock(MyLockOrder.FIRST);
   *
   * lockA.lock();
   *
   * lockB.lock();  // will throw an IllegalStateException
   * lockC.lock();  // will throw an IllegalStateException
   *
   * lockA.lock();  // reentrant acquisition is okay
   * }

package org.apache.maven.api;

import java.time.Clock;
import java.time.Duration;
import java.time.Instant;
import java.time.ZoneId;
import java.time.ZoneOffset;

/**
 * A Clock implementation that combines monotonic timing with wall-clock time.
 * <p>
 * This class provides precise time measurements using {@link System#nanoTime()}
 * while maintaining wall-clock time information in UTC. The wall-clock time

		if err != nil {
			return err
		}
		pk.add(key.Kid, pkey)
	}

	return nil
}

func (pk *publicKeys) add(keyID string, key any) {
	pk.Lock()
	defer pk.Unlock()

	pk.pkMap[keyID] = key
}

func (pk *publicKeys) get(kid string) any {
	pk.RLock()
	defer pk.RUnlock()
	return pk.pkMap[kid]
}

// PopulatePublicKey - populates a new publickey from the JWKS URL.

     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      @GuardedBy("lock")
      private Future<@Nullable Void> currentFuture;

      SupplantableFuture(ReentrantLock lock, Future<@Nullable Void> currentFuture) {
        this.lock = lock;
        this.currentFuture = currentFuture;
      }

1FB00..1FB92  ; valid                  ;      ; NV8    # 13.0 BLOCK SEXTANT-1..UPPER HALF INVERSE MEDIUM SHADE AND LOWER HALF BLOCK
1FB93         ; disallowed                             # NA   <reserved-1FB93>
1FB94..1FBCA  ; valid                  ;      ; NV8    # 13.0 LEFT HALF INVERSE MEDIUM SHADE AND RIGHT HALF BLOCK..WHITE UP-POINTING CHEVRON

    void testClockTimezone() {
        MonotonicClock clock = MonotonicClock.get();

        assertEquals(ZoneOffset.UTC, clock.getZone(), "Clock should use UTC timezone");

        // Verify that attempting to change timezone returns the same instance
        Clock newClock = clock.withZone(ZoneId.systemDefault());
        assertSame(clock, newClock, "withZone() should return the same clock instance");
    }

    @Test

   */
  @GuardedBy("lock")
  private int runningTasks = 0;

  @GuardedBy("lock")
  private boolean shutdown = false;

  @Override
  public void execute(Runnable command) {
    startTask();
    try {
      command.run();
    } finally {
      endTask();
    }
  }

  @Override
  public boolean isShutdown() {
    synchronized (lock) {
      return shutdown;
    }
  }

    final Lock lock;

    LockingThread(Lock lock) {
      this.lock = lock;
    }

    @Override
    public void run() {
      lock.lock();
      try {
        locked.countDown();
        finishLatch.await(1, MINUTES);
      } catch (InterruptedException e) {
        fail(e.toString());
      } finally {
        lock.unlock();
      }
    }

			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	lock := syscall.Flock_t{
		Start:  0,
		Len:    0,
		Pid:    0,
		Type:   lockType,
		Whence: 0,
	}

	f, err := os.OpenFile(path, flag, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.FcntlFlock(f.Fd(), rlockType, &lock); err != nil {
		f.Close()
		if err == syscall.EAGAIN {
			err = ErrAlreadyLocked
		}

            }
        } finally {
            lock.writeLock().unlock();
        }
    }

    /**
     * Remove a child entry
     *
     * @param childName child file name
     */
    public void removeChild(String childName) {
        lock.writeLock().lock();
        try {
            if (children.remove(childName) != null) {