/**
     * Default constructor for index update callback implementation.
     * Creates a new instance with default values.
     */
    public IndexUpdateCallbackImpl() {
        // Default constructor
    }

    /** Atomic counter for the number of documents processed */
    protected AtomicLong documentSize = new AtomicLong(0);

    /** Total execution time for all operations */

. . .
```

Refer [Prometheus documentation](https://prometheus.io/docs/introduction/first_steps/) for more details.

### 2. Configure authentication type for Prometheus metrics

MinIO supports two authentication modes for Prometheus either `jwt` or `public`, by default MinIO runs in `jwt` mode. To allow public access without authentication for prometheus metrics set environment as follows.

```
export MINIO_PROMETHEUS_AUTH_TYPE="public"

import org.codelibs.fess.util.DocumentUtil;

/**
 * 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. */

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.web.admin.dict.kuromoji;

import org.lastaflute.web.validation.Required;

/**
 * The search form for Kuromoji.
 */
public class SearchForm {

    /**
     * Default constructor for SearchForm.
     */
    public SearchForm() {
    }

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.web.admin.dict.stemmeroverride;

import org.lastaflute.web.validation.Required;

/**
 * The search form for Stemmer Override.
 */
public class SearchForm {

    /**
     * Default constructor for SearchForm.
     */
    public SearchForm() {
    }

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.web.admin.dict.synonym;

import org.lastaflute.web.validation.Required;

/**
 * The search form for Synonym.
 */
public class SearchForm {

    /**
     * Default constructor for SearchForm.
     */
    public SearchForm() {
    }

		}

		// Transfer existing
		if !into.Compacted {
			for _, folder := range existingFolders {
				h := hashPath(folder.name)
				f.updateCache.copyWithChildren(&f.oldCache, h, folder.parent)
			}
		}
		// Scan new...
		for _, folder := range newFolders {
			h := hashPath(folder.name)
			// Add new folders to the update tree so totals update for these.
			if !into.Compacted {
				var foundAny bool

        // This method directly calls a superclass method (readResourceRecordWireFormat).
        // We need to setup fields to avoid NPE when parsing

        // Set recordName for parsing
        Field recordNameField = NameServicePacket.class.getDeclaredField("recordName");
        recordNameField.setAccessible(true);
        Name mockRecordName = new Name(mockConfig);

import org.jspecify.annotations.Nullable;

/**
 * GWT emulation of {@link com.google.common.collect.ImmutableMap}. For non sorted maps, it is a
 * thin wrapper around {@link java.util.Collections#emptyMap()}, {@link
 * Collections#singletonMap(Object, Object)} and {@link java.util.LinkedHashMap} for empty,
 * singleton and regular maps respectively. For sorted maps, it's a thin wrapper around {@link
 * java.util.TreeMap}.
 *
 * @see ImmutableSortedMap

  }

  /**
   * Invokes {@code consumer} once for each pair of <i>corresponding</i> elements in {@code streamA}
   * and {@code streamB}. If one stream is longer than the other, the extra elements are silently
   * ignored. Elements passed to the consumer are guaranteed to come from the same position in their
   * respective source streams. For example:
   *
   * {@snippet :
   * Streams.forEachPair(