public void test_generate_withValidThumbnailId() {
        // Test successful thumbnail generation
        String thumbnailId = "test-thumbnail-001";
        assertTrue(thumbnailGenerator.generate(thumbnailId, tempOutputFile));
        assertTrue(tempOutputFile.exists());
    }

    public void test_generate_withNullThumbnailId() {
        // Test generation with null thumbnail ID
        assertFalse(thumbnailGenerator.generate(null, tempOutputFile));

/**
 * Abstract base class for thumbnail generators.
 * Provides common functionality for thumbnail generation implementations.
 */
public abstract class BaseThumbnailGenerator implements ThumbnailGenerator {
    private static final Logger logger = LogManager.getLogger(BaseThumbnailGenerator.class);

    /** Map of conditions for thumbnail generation. */
    protected final Map<String, String> conditionMap = new HashMap<>();

    protected final List<ThumbnailGenerator> generatorList = new ArrayList<>();

    /**
     * Queue for thumbnail generation tasks containing URL, content, and path tuples.
     */
    protected BlockingQueue<Tuple3<String, String, String>> thumbnailTaskQueue;

    /**
     * Flag indicating whether thumbnail generation is currently in progress.
     */
    protected volatile boolean generating;

    private Thread thumbnailQueueThread;

     * This implementation is empty as no cleanup is required.
     */
    @Override
    public void destroy() {
    }

    /**
     * Creates a thumbnail generation task for the specified document.
     *
     * @param path the file path or URL of the document
     * @param docMap the document metadata map containing field values

 */
public class GenerateThumbnailJob extends ExecJob {
    /** Logger for this class. */
    static final Logger logger = LogManager.getLogger(GenerateThumbnailJob.class);

    /** Number of threads to use for thumbnail generation. */
    protected int numOfThreads = 1;

    /** Flag indicating whether to perform cleanup operations. */
    protected boolean cleanup = false;

    /**
     * Default constructor for the GenerateThumbnailJob.

 */
public class CommandGenerator extends BaseThumbnailGenerator {
    private static final Logger logger = LogManager.getLogger(CommandGenerator.class);

    /** List of command strings to execute for thumbnail generation. */
    protected List<String> commandList;

    /** Timeout for command execution in milliseconds. */
    protected long commandTimeout = 30 * 1000L;// 30sec

        new File(tempDir, "WEB-INF/plugin").mkdirs();

        thumbnailJob.numOfThreads(2);

        testProcessHelper.exitValue = 0;
        testProcessHelper.processOutput = "Thumbnail generation completed";

        String result = thumbnailJob.execute();

        assertNotNull(result);
        // The result should contain Session Id with the generated session ID

     * When enabled, a login link is shown to unauthenticated users.
     */
    @Size(max = 10)
    public String loginLink;

    /**
     * Enable or disable thumbnail generation for documents.
     * When enabled, thumbnails are generated for supported file types.
     */
    @Size(max = 10)
    public String thumbnail;

    /**

    /** Helper for performing search operations and managing search requests. */
    @Resource
    protected SearchHelper searchHelper;

    /** Manager for handling thumbnail generation and display. */
    @Resource
    protected ThumbnailManager thumbnailManager;

    /** Helper for managing label types and label-based filtering. */
    @Resource
    protected LabelTypeHelper labelTypeHelper;

- **XML Processing** (`org.codelibs.core.xml`) - XML DOM utilities, SAX parser helpers, and schema validation support
- **SQL Utilities** (`org.codelibs.core.sql`) - JDBC helper methods for result sets, prepared statements, and connection management
- **Network & I/O** (`org.codelibs.core.net`, `org.codelibs.core.nio`) - URL utilities, UUID generation, MIME type detection, and NIO channel operations