*
     * @param sessionId the session ID whose data should be deleted
     */
    private void deleteBySessionId(final String sessionId) {
        try {
            urlFilterService.delete(sessionId);
        } catch (final Exception e) {
            logger.warn("Failed to delete UrlFilter: sessionId={}", sessionId, e);
        }
        try {

    /** Info map key for data index size. */
    public static final String DATA_INDEX_SIZE = "DataIndexSize";

    /** Session identifier key. */
    public static final String SESSION_ID = "sessionId";

    /** Crawling information identifier key. */
    public static final String CRAWLING_INFO_ID = "crawlingInfoId";

    /** Indexing target identifier key. */

        assertEquals(0, patterns.size());
    }

    public void test_delete_multipleSessions() {
        final String sessionId1 = "session7";
        final String sessionId2 = "session8";

        urlFilterService.addIncludeUrlFilter(sessionId1, "http://example.com/.*");
        urlFilterService.addIncludeUrlFilter(sessionId2, "http://test.com/.*");

            crawler2.getCrawlerContext().setNumOfThread(numOfThread);

            final String sessionId1 = crawler1.execute();
            final String sessionId2 = crawler2.execute();

            assertNotSame(sessionId1, sessionId2);
            assertNotSame(crawler1.crawlerContext, crawler2.crawlerContext);

            for (int i = 0; i < 100; i++) {

            crawler2.getCrawlerContext().setNumOfThread(numOfThread);

            final String sessionId1 = crawler1.execute();
            final String sessionId2 = crawler2.execute();

            assertNotSame(sessionId1, sessionId2);
            assertNotSame(crawler1.crawlerContext, crawler2.crawlerContext);

            // Wait for both crawlers to start with polling

        preauthService.initializeSession(sessionId, salt, PreauthIntegrityService.HASH_ALGO_SHA512);

        // Simulate message exchange
        preauthService.updatePreauthHash(sessionId, "Message1".getBytes());
        preauthService.updatePreauthHash(sessionId, "Message2".getBytes());

        byte[] expectedHash = preauthService.getCurrentPreauthHash(sessionId);

        // Validation should pass with correct hash

            crawler2.getCrawlerContext().setNumOfThread(numOfThread);

            final String sessionId1 = crawler1.execute();
            final String sessionId2 = crawler2.execute();

            assertNotSame(sessionId1, sessionId2);
            assertNotSame(crawler1.crawlerContext, crawler2.crawlerContext);

            // Wait for both crawlers to start with polling

        assertArrayEquals(testKey, rawKey2, "Should still match original");
    }

    @Test
    public void testRemoveSessionKey() {
        String sessionId = "test-session-3";
        keyManager.storeSessionKey(sessionId, testKey, "AES");

        assertTrue(keyManager.hasSessionKey(sessionId), "Key should exist");

        keyManager.removeSessionKey(sessionId);

        crawler.crawlerContext.setNumOfThread(5);
        crawler.urlFilter.addInclude("https://example.com/.*");
        
        // Execute crawling
        String sessionId = crawler.execute();
        System.out.println("Crawling completed. Session ID: " + sessionId);
    }
}
```

### File System Crawling

```java
import org.codelibs.fess.crawler.client.fs.FileSystemClient;

// Configure for file system crawling

        // Store in memory
        sessionKeys.put(sessionId, secretKey);
        rawKeys.put(sessionId, keyClone);

        // Track creation time for rotation (only for non-archived keys)
        if (!sessionId.contains(".v")) {
            keyCreationTimes.put(sessionId, System.currentTimeMillis());
            keyVersions.putIfAbsent(sessionId, 0);
        }

        // Optionally store in KeyStore