if m.handlers.hasSubhandler(subID) && !id.isTestHandler() {
		return fmt.Errorf("handler %v, subroute:%v: %w", id.String(), s, ErrHandlerAlreadyExists)
	}
	m.handlers.subSingle[subID] = h
	// Copy so clients can also pick it up for other subpaths.
	m.handlers.subSingle[makeZeroSubHandlerID(id)] = h
	return nil
}

/*
// RegisterStateless will register a stateless handler that serves
// []byte -> stream of ([]byte, error) requests.

import org.codelibs.fess.Constants;
import org.codelibs.fess.app.web.CrudMode;
import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;

/**
 * Unit tests for {@link AdminUserAction}.
 * Tests user management action logic including password validation, form handling, and CRUD modes.
 */
public class AdminUserActionTest extends UnitFessTestCase {

import static org.hamcrest.CoreMatchers.not;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertThat;

import org.junit.Test;

/**
 * Tests for {@link CachedCipher}.
 */
public class CachedCipherTest {

    @Test
    public void testEncryptDecryptBytes() {
        final CachedCipher cipher = new CachedCipher();
        cipher.setKey("mySecretKey");

import static org.junit.jupiter.api.Assertions.assertTrue;

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.mockito.MockitoAnnotations;

/**
 * Unit tests for the {@link TransWaitNamedPipe} transaction.
 * The transaction is package private, so the test class lives in the
 * same package to access its fields.
 */
public class TransWaitNamedPipeTest {

    @BeforeEach

import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Unit test for {@link TestLogHandler}.
 *
 * @author kevinb
 */
@NullUnmarked
public class TestLogHandlerTest extends TestCase {

  private TestLogHandler handler;
  private final TearDownStack stack = new TearDownStack();

import com.google.common.annotations.GwtCompatible;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;

/**
 * Implementation helper for {@link TestMapGenerator} for use with enum maps.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public abstract class TestEnumMapGenerator implements TestMapGenerator<AnEnum, String> {

  @Override

import com.google.common.collect.ImmutableBiMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;

/**
 * Generators of various {@link com.google.common.collect.BiMap}s and derived collections.
 *
 * @author Jared Levy
 * @author Hayward Chan
 */
@GwtCompatible
@NullMarked
public class BiMapGenerators {

import java.util.NoSuchElementException;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code element()} operations on a queue. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code peek()} operations on a queue. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests addAll operations on a set. Can't be invoked directly; please
 * see {@link com.google.common.collect.testing.SetTestSuiteBuilder}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")