System.out.printf("  Avg atomic operation time: %.2f ns%n", avgOpTimeNs);

        // Verify lock-free performance (allowing for JVM overhead)
        assertTrue(avgOpTimeNs < 5000, "Atomic operations should be reasonably fast (no lock contention)");
        assertEquals(threadCount * operationsPerThread, operations.get());

/*
 * Copyright (C) 2023 Block, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

    #  The definition for optimistic lock of DBFlute.
    #
    #; optimisticLockMap = map:{
    #    # o updateDateFieldName: (NotRequired - Default '')
    #    ; updateDateFieldName = UPDATE_DATE
    #
    #    # o versionNoFieldName: (NotRequired - Default 'VERSION_NO')
    #    #  The column name of version no for optimistic lock.

	if err != nil {
		return err
	}

	bootstrapTraceMsg("lookup the configuration")

	// Override any values from ENVs.
	lookupConfigs(srvCfg, objAPI)

	// hold the mutex lock before a new config is assigned.
	globalServerConfigMu.Lock()
	globalServerConfig = srvCfg
	globalServerConfigMu.Unlock()

	return nil

import java.util.Collection;
import java.util.Set;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * {@link Set} implementation that asserts that a given lock is held whenever one of its methods is
 * called.
 */
@NullUnmarked
class LockHeldAssertingSet<E> extends ForwardingSet<E> implements Serializable {
  final Set<E> delegate;
  final Object mutex;

	if err != nil {
		return err
	}
	defer resp.Body.Close()

	var accessToken Token
	if err = json.NewDecoder(resp.Body).Decode(&accessToken); err != nil {
		return err
	}

	k.Lock()
	k.accessToken = accessToken
	k.Unlock()
	return nil
}

// LookupUser lookup user by their userid.
func (k *KeycloakProvider) LookupUser(userid string) (User, error) {

    private static final String RO = Config.getProperty("jcifs.smb1.resolveOrder");

    private static LogStream log = LogStream.getInstance();

    private final Object LOCK = new Object();

    private final int lport;
    private int closeTimeout;
    private final byte[] snd_buf, rcv_buf;
    private DatagramSocket socket;
    private final DatagramPacket in, out;

   * Queue<E> queue = Queues.synchronizedQueue(MinMaxPriorityQueue.<E>create());
   * ...
   * queue.add(element);  // Needn't be in synchronized block
   * ...
   * synchronized (queue) {  // Must synchronize on queue!
   *   Iterator<E> i = queue.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {
   *     foo(i.next());
   *   }
   * }
   * }
   *

/*
 * Copyright (C) 2025 Block, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

            throw new IllegalArgumentException("Signature field exceeds data buffer size");
        }

        // Use fine-grained locking for better concurrency
        this.signingLock.lock();
        try {
            if (this.closed) {
                throw new IllegalStateException("SigningDigest is closed");
            }

            // zero out signature field