} catch (InterruptedException e) {
                    log.debug("Async notification monitoring interrupted for {}", registrationId);
                    Thread.currentThread().interrupt();
                    break;
                } catch (Exception e) {
                    log.debug("Error in async notification monitoring for {}: {}", registrationId, e.getMessage());

import org.dbflute.mail.send.supplement.async.SMailAsyncStrategy;
import org.dbflute.mail.send.supplement.filter.SMailSubjectFilter;
import org.dbflute.mail.send.supplement.label.SMailLabelStrategy;
import org.dbflute.optional.OptionalThing;
import org.dbflute.util.DfStringUtil;
import org.lastaflute.core.magic.async.AsyncManager;
import org.lastaflute.core.magic.async.ConcurrentAsyncCall;

            byte[] buffer = new byte[256];
            System.arraycopy(SMBUtil.SMB2_HEADER, 0, buffer, 0, 4);
            // Set up async message fields
            SMBUtil.writeInt4(ServerMessageBlock2.SMB2_FLAGS_ASYNC_COMMAND, buffer, 16); // flags with async
            SMBUtil.writeInt8(789L, buffer, 32); // async ID
            SMBUtil.writeInt8(456L, buffer, 40); // session ID
            return buffer;
        }

        assertEquals(asyncId, request.getAsyncId());
        assertTrue((request.getFlags() & SMB2_FLAGS_ASYNC_COMMAND) != 0, "Async flag should be set when asyncId is non-zero");
    }

    @Test
    @DisplayName("Test constructor with zero asyncId does not set async flag")
    void testConstructorWithZeroAsyncId() {
        // Given
        long mid = 12345L;
        long asyncId = 0L;

        // When

                throw new RuntimeException(e);
            }
        }

        @Override
        public boolean isAsync() {
            return async;
        }

        public void setAsync(boolean async) {
            this.async = async;
        }

        @Override
        public boolean isRetainPayload() {
            return retainPayload;
        }

        statusField.setInt(smb, status);
    }

    private void setAsync(ServerMessageBlock2 smb, boolean async) throws Exception {
        Field asyncField = ServerMessageBlock2.class.getDeclaredField("async");
        asyncField.setAccessible(true);
        asyncField.setBoolean(smb, async);
    }

├── concurrent/                 # Async patterns (Deferred/Promise)
└── util/                      # Utilities
```

### Key Design Patterns

- **Builder**: SuggesterBuilder, SuggestRequestBuilder
- **Facade**: Suggester (main entry point)
- **Composite**: NormalizerChain, ReadingConverterChain
- **Strategy**: Normalizer, ReadingConverter, ContentsParser
- **Deferred/Promise**: Async operations

### Index Alias Strategy

        if ((this.flags & SMB2_FLAGS_ASYNC_COMMAND) == SMB2_FLAGS_ASYNC_COMMAND) {
            // async
            this.async = true;
            this.asyncId = SMBUtil.readInt8(buffer, bufferIndex);
            bufferIndex += 8;
        } else {
            // sync
            this.async = false;
            bufferIndex += 4; // reserved
            this.treeId = SMBUtil.readInt4(buffer, bufferIndex);

            return this.notifyInformation;
        }

        @Override
        public boolean isAsync() {
            return this.async;
        }

        public void setAsync(boolean async) {
            this.async = async;
        }

        @Override
        public CommonServerMessageBlockResponse getNextResponse() {
            return this.nextResponse;
        }

        when(request.allowChain(any())).thenReturn(true);

        // When
        boolean async = request.isResponseAsync();
        int size = request.size();
        Integer timeout = request.getOverrideTimeout();
        boolean canChain = request.allowChain(nextRequest);

        // Then
        assertTrue(async);
        assertEquals(100, size);
        assertEquals(3000, timeout);
        assertTrue(canChain);