CrawlerEngineClient client = new CrawlerEngineClient();
            assertNotNull(client);
        }
    }

    // Test instance fields initialization
    @Test
    public void test_instanceFieldsInitialization() {
        // Test that instance fields are properly initialized
        assertNotNull(crawlerEngineClient);
        // The actual client initialization happens lazily when needed
    }

Below is the protocol in some more detail:

1. The client looks for a compatible idle daemon. If there isn't one, it starts a new daemon.
2. The client connects to the idle daemon and sends it a request to do some work. If the daemon is no longer running, the client starts again.
3. If the daemon is not able to run the request, for example it is already running a request or is shutting down, it rejects the request. The client starts again.

        final List<Map<String, Object>> fileList = new ArrayList<>();

        try (final StorageClient client = StorageClientFactory.createClient(fessConfig)) {
            // Ensure bucket exists on first access
            client.ensureBucketExists();

            final List<StorageItem> items = client.listObjects(prefix, fessConfig.getStorageMaxItemsInPageAsInteger());

            for (final StorageItem item : items) {

        return $?
    fi
}

# Print command line usage / help
usage() {
    echo "Usage: $0 [-vdh] [-p pidfile] [-D prop] [-X prop]"
    echo "Start fess."
    echo "    -d            daemonize (run in background)"
    echo "    -p pidfile    write PID to <pidfile>"
    echo "    -h"
    echo "    --help        print command line options"
    echo "    -v            print fess version, then exit"

    /**
     * Retrieves the appropriate crawler client for the given URL based on configured rules.
     * This method uses client rules to determine which specific client implementation
     * should be used for crawling the URL, falling back to the default client if no
     * specific rule matches.
     *
     * @param url the URL to get a client for
     * @return the crawler client instance to use for the URL
     */
    @Override

* The [Gradle Tooling API client](https://docs.gradle.org/8.8/userguide/third_party_integration.html#embedding)
  * This requires a Java application, and thus runtime, to run the tooling API client

As indicated, each of those components require a Java runtime to run.

The recommended way of invoking Gradle is to use the Gradle Wrapper.

        return ComponentUtil.getFessConfig().isRateLimitEnabled();
    }

    /**
     * Get the client IP address from the request, considering proxy headers.
     * Only trusts X-Forwarded-For/X-Real-IP headers when the request comes from a trusted proxy.
     * @param request the HTTP request
     * @return the client IP address
     */
    public String getClientIp(final HttpServletRequest request) {

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.opensearch.client;

import static org.codelibs.core.stream.StreamUtil.split;

import org.codelibs.core.lang.StringUtil;
import org.codelibs.fesen.client.HttpClient;
import org.codelibs.fess.Constants;
import org.codelibs.fess.crawler.client.FesenClient;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.util.ComponentUtil;

    protected static final String VALUE_PREFIX = "field.value.";

    /** The script field prefix. */
    protected static final String SCRIPT_PREFIX = "field.script.";

    /** The client prefix. */
    protected static final String CLIENT_PREFIX = "client.";

    /** The config prefix. */
    protected static final String CONFIG_PREFIX = "config.";

    /** The field config prefix. */

    protected static final String ENTRAID_TENANT = "entraid.tenant";

    /** Configuration key for Entra ID client secret. */
    protected static final String ENTRAID_CLIENT_SECRET = "entraid.client.secret";

    /** Configuration key for Entra ID client ID. */
    protected static final String ENTRAID_CLIENT_ID = "entraid.client.id";

    /** Configuration key for Entra ID reply URL. */