The problem is that GWT responds poorly to two .gwt.xml files in the same
    Java package; see
    https://groups.google.com/g/google-web-toolkit-contributors/c/CqYH59Dt_rQ/m/uVGW1QdUsXUJ
    for details.

    The summary is that it ignores one file in favor of the other.
    util.concurrent, like nearly all our packages, has two .gwt.xml files: one

  <inherits name="com.google.common.net.Net" />
  <inherits name="com.google.common.primitives.Primitives" />
  <inherits name="com.google.common.util.concurrent.Concurrent" />
  <inherits name="com.google.common.xml.Xml" />
  <inherits name="com.google.thirdparty.publicsuffix.PublicSuffixPatterns" />
  <inherits name="com.google.thirdparty.publicsuffix.PublicSuffixType" />

  <!-- com.google.common.testing.Testing is located in

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN" 
	"http://dbflute.org/meta/lastadi10.dtd">
<components namespace="fessCrawler">
	<component name="crawlerConfig" class="org.codelibs.fess.crawler.util.FessCrawlerConfig">
		<property name="queueIndex">"fess_crawler.queue"</property>
		<property name="queueShards">5</property>
		<property name="queueReplicas">1</property>

<?xml version="1.0" encoding="UTF-8"?>
<metadata>
  <groupId>org.codelibs.fess</groupId>
  <artifactId>fess-crawler-webdriver</artifactId>
  <versioning>
    <latest>3.16.0</latest>
    <release>3.16.0</release>
    <versions>
      <version>1.0.3</version>
      <version>1.0.4</version>
      <version>1.0.5</version>
      <version>1.0.6</version>
      <version>1.0.7</version>
      <version>1.0.8</version>
      <version>1.0.9</version>

Yuri Schimke <******@****.***> 1605965325 +0000

        osddHelper.setOsddPath("osdd/osdd.xml");
        osddHelper.setContentType("text/xml");
        osddHelper.init();
        assertTrue(osddHelper.hasOpenSearchFile());

        osddHelper.setContentType("application/opensearchdescription+xml");
        final StreamResponse streamResponse = osddHelper.asStream();
        assertEquals("application/opensearchdescription+xml; charset=UTF-8", streamResponse.getContentType());
    }

 * outside the ASCII character range. Unlike HTML escaping the XML escapers will not escape
 * non-ASCII characters to their numeric entity replacements. These XML escapers provide the minimal
 * level of escaping to ensure that the output can be safely included in a Unicode XML document.
 *
 * <p>For details on the behavior of the escapers in this class, see sections <a
 * href="http://www.w3.org/TR/2008/REC-xml-20081126/#charsets">2.2</a> and <a

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.xml;

import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import javax.xml.XMLConstants;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.codelibs.core.exception.ParserConfigurationRuntimeException;

 */
package org.codelibs.core.xml;

import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.io.File;
import java.net.URL;

import javax.xml.transform.Source;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;

import org.codelibs.core.exception.SAXRuntimeException;
import org.xml.sax.SAXException;

/**

            ; esfluteDiFile = esflute_config.xml
        }
        ; fess_config.duplicate_host = map:{
            ; package = config
            ; esclientDiFile = esclient.xml
            ; esfluteDiFile = esflute_config.xml
        }
        ; fess_config.elevate_word = map:{
            ; package = config
            ; esclientDiFile = esclient.xml
            ; esfluteDiFile = esflute_config.xml
        }