# Directory Leasing Feature - Detailed Design Document

## 1. Overview

Directory leasing extends the SMB3 lease concept to directories, enabling client-side caching of directory metadata and change notifications. This significantly improves performance for applications that frequently enumerate directories or monitor directory changes.

## 2. Protocol Specification Reference

- **MS-SMB2 Section 2.2.13.2.12**: SMB2_CREATE_REQUEST_LEASE_V2 for directories

            assertEquals(0x1, Smb2Constants.SMB2_GLOBAL_CAP_DFS, "DFS capability must be 0x1");
        }

        @Test
        @DisplayName("Leasing capability should be 0x2")
        void testGlobalCapLeasing() {
            assertEquals(0x2, Smb2Constants.SMB2_GLOBAL_CAP_LEASING, "Leasing capability must be 0x2");
        }

        @Test
        @DisplayName("Large MTU capability should be 0x4")

     * @return lease key
     */
    public Smb2LeaseKey requestDirectoryLease(String directoryPath, int requestedState, DirectoryCacheScope scope) {
        // Directory leasing requires SMB 3.0 or higher
        // MS-SMB2: Level 2 leasing (which includes directory leasing) is only supported in SMB 3.0+
        // We'll validate this when we actually need to use the session

        // Request base lease

- Update `SmbSession` for multi-channel awareness
- Enhance `SmbTransport` for channel management

---

### Phase 4: Directory Leasing
**Priority: MEDIUM** | **Estimated Effort: 2-3 weeks**

Directory leasing extends the lease concept to directories for improved metadata caching.

#### 4.1 Core Directory Lease Infrastructure
```
Package: jcifs.internal.smb2.lease

                }
            } catch (NumberFormatException e) {
                // Invalid values ignored
            }
        }

        // Directory leasing configuration
        value = props.getProperty("jcifs.smb.client.useDirectoryLeasing");
        if (value != null) {
            this.useDirectoryLeasing = Boolean.parseBoolean(value);
        }

    protected int handleReconnectRetries = 3;
    /** Directory to store persistent handle state */
    protected String handleStateDirectory;

    // Directory leasing configuration fields
    /**
     * Whether to use directory leasing for cached directory listings
     */
    protected boolean useDirectoryLeasing = true;
    /**

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

import jcifs.internal.util.SMBUtil;
import jcifs.smb.SmbFile;

/**
 * Handles directory change notifications for SMB3 directory leasing
 */
public class DirectoryChangeNotifier {

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

    // Backoff and timing constants (in ms)

import org.mockito.Mock;
import org.mockito.MockitoAnnotations;

import jcifs.CIFSContext;
import jcifs.Configuration;
import jcifs.smb.SmbFile;

/**
 * Integration tests for directory leasing functionality
 */
public class DirectoryLeasingIntegrationTest {

    @Mock
    private CIFSContext context;

    @Mock
    private Configuration config;

    @Mock
    private SmbFile mockFile1;

        // Prepare test data with realistic SMB3 values
        byte[] buffer = new byte[50];
        int bufferIndex = 0;

        // SMB3 capabilities
        int testCapabilities = 0x0000002F; // DFS, LEASING, LARGE_MTU, MULTI_CHANNEL, PERSISTENT_HANDLES, DIRECTORY_LEASING

        // Random but realistic GUID

     */
    String getHandleStateDirectory();

    /**
     * Property {@code jcifs.smb.client.useDirectoryLeasing} (boolean, default true)
     *
     * @return whether to use directory leasing for caching
     */
    boolean isUseDirectoryLeasing();

    /**
     * Property {@code jcifs.smb.client.directoryCacheScope} (String, default "IMMEDIATE_CHILDREN")
     *