// Assert
        assertFalse(it.hasNext());
        verify(tree, times(1)).release();
    }

    @Test
    @DisplayName("doCloseInternal throwing still releases exactly once and next() recovers")
    void closeInternalThrowsButReleases() throws Exception {
        // Arrange
        stubAcquireReturnsSelf();
        FileEntry initial = entry("first");

        // Check if recovery is viable by testing if createTransport works
        // If createTransport returns null (no mock setup), remove immediately
        try {
            SmbTransport testTransport = manager.createTransport(failedChannel.getLocalInterface(), failedChannel.getRemoteInterface());
            if (testTransport == null) {
                // No recovery possible, remove synchronously

                log.warn("RDMA recovery attempt {} failed: {}", retryCount, recoveryError.getMessage());

                // If this was the last attempt, log the full error
                if (retryCount >= maxRetries) {
                    log.error("All RDMA recovery attempts failed", recoveryError);
                }
            }
        }

}
```

## 9. Error Handling and Fallback

### 9.1 RDMA Error Recovery
```java
public class RdmaErrorHandler {
    public void handleRdmaError(RdmaConnection connection, Exception error) {
        log.warn("RDMA error occurred: {}", error.getMessage());
        
        if (isRecoverableError(error)) {
            // Attempt to recover connection
            try {
                connection.reset();

                failoverStates.remove(channel.getChannelId());
                
                log.info("Successfully recovered channel {}", channel.getChannelId());
                
            } catch (Exception e) {
                log.warn("Failed to recover channel {}: {}", 
                    channel.getChannelId(), e.getMessage());
                
                // Schedule next retry or remove

     */
    public SmbException withContext(String key, Object value) {
        this.context.put(key, value);
        return this;
    }

    /**
     * Sets a recovery hint for the error
     *
     * @param hint the recovery hint
     * @return this exception for chaining
     */
    public SmbException withRecoveryHint(String hint) {
        this.recoveryHint = hint;
        return this;
    }

        
        PersistentHandleManager manager2 = new PersistentHandleManager(context);
        HandleInfo recovered = manager2.getHandleForReconnect("/test/file.txt");
        
        assertNotNull(recovered);
        assertEquals(HandleType.PERSISTENT, recovered.type);
        assertArrayEquals(fileId, recovered.fileId);
    }
}
```

### 8.2 Integration Tests
```java
@Test

import org.codelibs.fess.util.ComponentUtil;
import org.opensearch.index.query.QueryBuilder;
import org.opensearch.index.query.QueryBuilders;

/**
 * Job for purging expired documents from the search index.
 * This job removes documents that have passed their expiration time based on the expires field.
 * It helps maintain the search index by cleaning up outdated content automatically.
 */
public class PurgeDocJob {

        return URL_QUEUE_SERVICE_THREAD_LOCAL.get();
    }

    /**
     * Sets the UrlQueueService instance to the thread-local variable.
     * If the provided UrlQueueService is null, it removes the current instance from the thread-local variable.
     *
     * @param urlQueueService the UrlQueueService instance to be set, or null to remove the current instance
     */

     *         element.
     */
    @Override
    public boolean add(final E o) {
        return map.put(o, PRESENT) == null;
    }

    /**
     * Removes the specified element from this set if it is present.
     *
     * @param o
     *            object to be removed from this set, if present.
     * @return true if the set contained the specified element.
     */