return new SmbFileInputStream(mockFile, mockTree, mockHandle);
    }

    @BeforeEach
    void setUp() throws Exception {
        // Common, safe defaults for collaborators
        when(mockHandle.isValid()).thenReturn(true);
        when(mockHandle.acquire()).thenReturn(mockHandle);
        when(mockHandle.getTree()).thenReturn(mockTree);

    }

    @Test
    public void test_createIndexIfNothing_multipleCallsAreSafe() throws Exception {
        Suggester suggester = createSuggester();

        // Multiple consecutive calls should be safe
        suggester.createIndexIfNothing();
        suggester.createIndexIfNothing();
        suggester.createIndexIfNothing();

        // Should still be able to use the index
        suggester.refresh();

        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
    return added;
  }

  /**
   * Returns a synchronized (thread-safe) queue backed by the specified queue. In order to guarantee
   * serial access, it is critical that <b>all</b> access to the backing queue is accomplished
   * through the returned queue.
   *

      subgraph.addNode(node);
    }
    for (N node : subgraph.nodes()) {
      for (N successorNode : graph.successors(node)) {
        if (subgraph.nodes().contains(successorNode)) {
          // requireNonNull is safe because the endpoint pair comes from the graph.
          subgraph.putEdgeValue(
              node,
              successorNode,
              requireNonNull(graph.edgeValueOrDefault(node, successorNode, null)));

        return o != null;
      }

      @Override
      public String toString() {
        return "Predicates.notNull()";
      }
    };

    @SuppressWarnings("unchecked") // safe contravariant cast
    <T extends @Nullable Object> Predicate<T> withNarrowedType() {
      return (Predicate<T>) this;
    }
  }

  /**
   * @see Predicates#not(Predicate)
   */

 * are stored in the cache until either evicted or manually invalidated. The common way to build
 * instances is using {@link CacheBuilder}.
 *
 * <p>Implementations of this interface are expected to be thread-safe, and can be safely accessed
 * by multiple concurrent threads.
 *
 * <p>When evaluated as a {@link Function}, a cache yields the same result as invoking {@link
 * #getUnchecked}.
 *

 *
 * Features:
 * - Encrypts credentials at rest using AES-256-GCM
 * - Uses PBKDF2 for key derivation from master password
 * - Secure wiping of sensitive data
 * - Thread-safe operations
 * - Protection against timing attacks
 */
public class SecureCredentialStorage implements AutoCloseable, Destroyable {

    private static final Logger log = LoggerFactory.getLogger(SecureCredentialStorage.class);

			// Expect header is always of form:
			//
			//   Expect       =  "Expect" ":" 1#expectation
			//   expectation  =  "100-continue" | expectation-extension
			//
			// So it safe to assume that '100-continue' is what would
			// be sent, for the time being keep this work around.
			// Adding a *TODO* to remove this later when Golang server
			// doesn't filter out the 'Expect' header.

        assertTrue(item1.equals(item2));
        assertTrue(item2.equals(item1));
    }

    @Test
    public void test_equals_withNullInput() {
        // Test equals with null input - should not throw, uses null-safe comparison
        ProtwordsItem item1 = new ProtwordsItem(1, null);
        ProtwordsItem item2 = new ProtwordsItem(2, null);
        ProtwordsItem item3 = new ProtwordsItem(1, "word");

        queue.add(event, label);
      }
    }
  }

  /**
   * Dispatches all events enqueued prior to this call, serially and in order, for every listener.
   *
   * <p>Note: this method is idempotent and safe to call from any thread
   */
  public void dispatch() {
    // iterate by index to avoid concurrent modification exceptions
    for (int i = 0; i < listeners.size(); i++) {
      listeners.get(i).dispatch();
    }