GsaConfigException exception = new GsaConfigException(null);

        assertNotNull(exception);
        assertNull(exception.getMessage());
        assertNull(exception.getCause());
    }

    @Test
    public void test_constructorWithNullMessageAndCause() {
        // Test constructor with null message and null cause
        GsaConfigException exception = new GsaConfigException(null, null);

        try {
            parser.parse(new InputSource(new StringReader(invalidXml)));
            fail("Should throw GsaConfigException");
        } catch (GsaConfigException e) {
            assertEquals("Failed to parse XML file.", e.getMessage());
        }
    }

    @Test
    public void test_parseWithMalformedXml() {

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.exception.GsaConfigException;
import org.codelibs.fess.opensearch.config.exentity.FileConfig;
import org.codelibs.fess.opensearch.config.exentity.LabelType;
import org.codelibs.fess.opensearch.config.exentity.WebConfig;