@Test
    public void test_multiple_commands_configuration() throws Exception {
        // Test setting multiple commands without triggering execution
        final List<String> commands =
                Arrays.asList("command1 ${url} ${outputFile}", "command2 ${url} ${outputFile}", "command3 ${url} ${outputFile}");

        generator.setCommandList(commands);

    }

    /**
     * Executes an external command with the given parameters.
     * @param commands The command array to execute.
     * @param username The username parameter for the command.
     * @param password The password parameter for the command.
     * @return The exit code of the executed command.
     */
    protected int executeCommand(final String[] commands, final String username, final String password) {

import jakarta.annotation.PostConstruct;

/**
 * Query processor component that handles query filters and commands.
 * This class provides a pipeline for processing Lucene queries by applying
 * a chain of filters and executing registered query commands.
 *
 * <p>The processor maintains a map of query commands indexed by query class names
 * and a list of filters that are applied in order during query processing.</p>
 */

import jakarta.annotation.PostConstruct;

/**
 * Command-based thumbnail generator that executes external commands to create thumbnails.
 * Uses external tools through command execution to generate thumbnail images from documents.
 */
public class CommandGenerator extends BaseThumbnailGenerator {
    private static final Logger logger = LogManager.getLogger(CommandGenerator.class);

    /** List of command strings to execute for thumbnail generation. */

| Search Engine | OpenSearch |
| App Server | Embedded Tomcat |
| Crawler | fess-crawler library |
| Scheduler | Lasta Job |
| Logging | Log4j2 |
| Testing | JUnit 4/5, UTFlute, REST Assured |

## Development Commands

### Setup
```bash
mvn antrun:run          # Download OpenSearch plugins (required before first build)
mvn dbflute:download    # One-time setup for DBFlute
mvn dbflute:freegen     # Generate DBFlute source code

### Download and Install/Run

Fess 15.5 is now available and can be downloaded on the [Releases page](https://github.com/codelibs/fess/releases "download"). Downloads come in 3 flavors: deb, rpm, zip.

The following commands show how to use the zip download:

    $ unzip fess-15.5.x.zip
    $ cd fess-15.5.x
    $ ./bin/fess

For more details, see the [Installation Guide](https://fess.codelibs.org/15.5/install/index.html).

### Docker

            assertNotNull(jobProcess2);
            // Since echo command completes quickly, processes might already be finished
            // So we just verify that processes were created without errors

            Set<String> sessionIds = processHelper.getRunningSessionIdSet();
            // Since echo commands complete quickly, we may not catch them running
            // Just verify no exceptions occurred

        }
    }

    private static ExecResult exec(String[] command) throws IOException, InterruptedException, ExecutionException {
        Objects.requireNonNull(command, "command");
        if (command.length == 0) {
            throw new IllegalArgumentException("command must not be empty");
        }

        ProcessBuilder pb = new ProcessBuilder(command);
        Process process = pb.start();

    protected void setUpChild() throws Exception {
        // Get the queryProcessor that was registered in parent class
        queryProcessor = ComponentUtil.getComponent("queryProcessor");

        // Register all query commands needed for testing
        new TermQueryCommand().register();
        new MatchAllQueryCommand().register();
        new PhraseQueryCommand().register();
        new BooleanQueryCommand().register();

        lastaEnv = env;
        return this;
    }

    /**
     * Adds a system property to the command list.
     * If the property exists in the system, it uses that value with optional append value.
     * Otherwise, it uses the default value if provided.
     *
     * @param cmdList the command list to add the property to
     * @param name the property name