this.lock = new ReentrantReadWriteLock();

        // Start cleanup executor for expired leases
        this.cleanupExecutor = Executors.newSingleThreadScheduledExecutor(r -> {
            Thread t = new Thread(r, "LeaseManager-Cleanup");
            t.setDaemon(true);
            return t;
        });

        // Schedule periodic cleanup
        long cleanupInterval = context.getConfig().getLeaseTimeout();

    if (value != null) {
      return value;
    }

    // Store a local reference to the cache entry. If the backing map is immutable, this,
    // in combination with immutable cache entries, will ensure a thread-safe cache.
    CacheEntry<K, V> entry;

    // Check cache. We use == on purpose because it's cheaper and a cache miss is ok.
    entry = cacheEntry1;
    if (entry != null && entry.key == key) {

     * implementations, supports add() under JDK8. This seems problematic, but I
     * didn't see that discussed in the review, which included many other
     * changes: https://mail.openjdk.org/pipermail/core-libs-dev/2013-May/thread.html#17367
     *
     * TODO(cpovirk): decide what the best long-term action here is: force users
     * to suppress (as we do now), stop testing entrySet().add() at all, make

      @Override
      public void run() {}
    }

    @Keep
    public static final class DummyThreadFactory implements ThreadFactory, Serializable {
      @Override
      public Thread newThread(Runnable r) {
        return new Thread(r);
      }
    }

    @Keep
    public static final class DummyExecutor implements Executor, Serializable {
      @Override
      public void execute(Runnable command) {}
    }

/**
 * A record representing the result of a single request operation, containing the original request,
 * the result (if successful), and any error that occurred during processing.
 * <p>
 * This class is immutable and thread-safe, suitable for use in concurrent operations.
 *
 * @param <REQ> The type of the request
 * @param <REP> The type of the response, which must extend {@code Result<REQ>}
 * @param request The original request that was processed

     * Search criteria: target URLs.
     */
    public String urls;

    /**
     * Search criteria: user agent string.
     */
    public String userAgent;

    /**
     * Search criteria: number of threads.
     */
    public String numOfThread;

    /**
     * Search criteria: interval time.
     */
    public String intervalTime;

    /**
     * Search criteria: boost value.
     */

   * proceed to read the response body with [Response.body]. The response is still live until its
   * response body is [closed][ResponseBody]. The recipient of the callback may consume the response
   * body on another thread.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP

        buf.append(",\"service.name\":\"").append(ecsServiceName).append('"');
        buf.append(",\"event.dataset\":\"").append(ecsEventDataset).append('"');
        buf.append(",\"process.thread.name\":\"").append(StringEscapeUtils.escapeJson(Thread.currentThread().getName())).append('"');
        buf.append(",\"log.logger\":\"").append(StringEscapeUtils.escapeJson(this.getClass().getName())).append('"');
        valueMap.entrySet()

 * contract.
 *
 * <p>The {@code standard} methods and the collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Louis Wasserman
 * @since 12.0
 */
@GwtIncompatible
public abstract class ForwardingNavigableSet<E extends @Nullable Object>

import java.util.concurrent.atomic.AtomicReference;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Simplified circuit breaker implementation for SMB operations.
 * Thread-safe and lock-free implementation to prevent cascading failures.
 *
 * Features:
 * - Simple state management (CLOSED, OPEN, HALF_OPEN)
 * - Lock-free atomic operations
 * - Configurable thresholds and timeouts