*/
    public static String concatName(final String s1, final String s2) {
        if (StringUtil.isEmpty(s1) && StringUtil.isEmpty(s2)) {
            return null;
        }
        if (!StringUtil.isEmpty(s1) && StringUtil.isEmpty(s2)) {
            return s1;
        }
        if (StringUtil.isEmpty(s1) && !StringUtil.isEmpty(s2)) {
            return s2;
        }
        return s1 + '.' + s2;
    }

    @Override
    public synchronized void delete(final StemmerOverrideItem item) {
        final StemmerOverrideItem stemmerOverrideItem = item;
        stemmerOverrideItem.setNewInput(StringUtil.EMPTY);
        stemmerOverrideItem.setNewOutput(StringUtil.EMPTY);
        try (StemmerOverrideUpdater updater = new StemmerOverrideUpdater(item)) {
            reload(updater);
        }
    }

    /**

import org.apache.logging.log4j.Logger;
import org.codelibs.core.concurrent.CommonPoolUtil;
import org.codelibs.core.io.CloseableUtil;
import org.codelibs.core.io.CopyUtil;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.InputStreamThread;

import jakarta.annotation.PostConstruct;

/**

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.crawler.util;

import java.util.Map;
import java.util.regex.Pattern;

import org.codelibs.core.lang.StringUtil;
import org.codelibs.core.stream.StreamUtil;
import org.codelibs.fess.Constants;
import org.dbflute.optional.OptionalThing;

/**
 * Utility class for managing field configurations with parameter mappings.

import java.util.UUID;
import java.util.function.Supplier;
import java.util.stream.Collectors;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.Constants;
import org.codelibs.fess.app.web.api.ApiResult;
import org.codelibs.fess.app.web.api.ApiResult.ApiErrorResponse;
import org.codelibs.fess.app.web.api.ApiResult.Status;

        switch (form.crudMode) {
        case CrudMode.CREATE:
            final KuromojiItem entity = new KuromojiItem(0, StringUtil.EMPTY, StringUtil.EMPTY, StringUtil.EMPTY, StringUtil.EMPTY);
            return OptionalEntity.of(entity);
        case CrudMode.EDIT:
            if (form instanceof EditForm) {

    }

    private static String[] splitLine(final String value) {
        if (StringUtil.isBlank(value)) {
            return StringUtil.EMPTY_STRINGS;
        }
        final String[] values = value.split("[\r\n]");
        final List<String> list = new ArrayList<>(values.length);
        for (final String line : values) {
            if (StringUtil.isNotBlank(line)) {
                list.add(line.trim());
            }

import java.util.Locale;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.io.CopyUtil;
import org.codelibs.core.io.ReaderUtil;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.curl.CurlRequest;
import org.codelibs.curl.CurlResponse;
import org.codelibs.fess.Constants;
import org.codelibs.fess.annotation.Secured;
import org.codelibs.fess.app.web.base.FessAdminAction;

import java.util.stream.Stream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.core.stream.StreamUtil;
import org.codelibs.fess.exception.ThemeException;
import org.codelibs.fess.helper.PluginHelper.Artifact;
import org.codelibs.fess.helper.PluginHelper.ArtifactType;

import java.util.List;
import java.util.Map;

import org.apache.commons.lang3.RandomStringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.core.timer.TimeoutTask;
import org.codelibs.fess.Constants;
import org.codelibs.fess.exception.JobProcessingException;
import org.codelibs.fess.helper.ProcessHelper;