package once

// Singleton contains a pointer to T that must be set once.
// Until the value is set all Get() calls will block.
type Singleton[T any] struct {
	v   *T
	set chan struct{}
}

// NewSingleton creates a new unset singleton.
func NewSingleton[T any]() *Singleton[T] {
	return &Singleton[T]{set: make(chan struct{}), v: nil}
}

// Get will return the singleton value.
func (s *Singleton[T]) Get() *T {
	<-s.set
	return s.v

    }

    public void setVersionNo(final Long version) {
        asDocMeta().version(version);
    }

    public org.codelibs.fess.crawler.client.http.RequestHeader getCrawlerRequestHeader() {
        return new org.codelibs.fess.crawler.client.http.RequestHeader(getName(), getValue());
    }

    public WebConfig getWebConfig() {
        if (webConfig == null) {

  /**
   * Invoked on a background thread after the referent has been garbage collected unless security
   * restrictions prevented starting a background thread, in which case this method is invoked when
   * new references are created.
   */
  void finalizeReferent();

    @Override
    public Optional<CIInfo> detectCI() {
        String ciEnv = System.getenv(CIRCLECI);
        if ("true".equals(ciEnv)) {
            return Optional.of(new CIInfo() {
                @Override
                public String name() {
                    return NAME;
                }
            });
        }
        return Optional.empty();
    }

    @Override
    public Optional<CIInfo> detectCI() {
        String workspace = System.getenv(WORKSPACE);
        if (workspace != null && !workspace.trim().isEmpty()) {
            return Optional.of(new CIInfo() {
                @Override
                public String name() {
                    return NAME;
                }
            });
        }
        return Optional.empty();
    }

        Map<String, Object> userData = (Map<String, Object>) context.getUserData();
        userData.put("acceptedApiChanges", acceptedApiChanges);
        userData.put("seenApiChanges", new HashSet<ApiChange>());
    }

@NullUnmarked
public final class InvalidatableSetTest {
  Set<Integer> wrappedSet;
  Set<Integer> copyOfWrappedSet;
  InvalidatableSet<Integer> setToTest;

  @Before
  public void createSets() {
    wrappedSet = new HashSet<>();
    wrappedSet.add(1);
    wrappedSet.add(2);
    wrappedSet.add(3);

    copyOfWrappedSet = ImmutableSet.copyOf(wrappedSet);
    setToTest =

/**
 * @author taichi
 */
public class LruHashMapTest {

    /**
     * @throws Exception
     */
    @Test
    public void testAll() throws Exception {
        final LruHashMap<String, String> lru = new LruHashMap<String, String>(3);
        lru.put("aaa", "111");
        lru.put("bbb", "222");
        lru.put("ccc", "333");
        assertThat(lru.get("aaa"), is("111"));
        Iterator<String> i = lru.keySet().iterator();

    }

    @Override
    public TokenStream create(final TokenStream tokenStream) {
        if (keywordPath == null) {
            return tokenStream;
        }
        return new ReloadableKeywordMarkerFilter(tokenStream, keywordPath, reloadInterval);
    }

    }

    @Override
    public TokenStream create(final TokenStream tokenStream) {
        if (stopwordPath == null) {
            return tokenStream;
        }
        return new ReloadableStopFilter(tokenStream, stopwordPath, ignoreCase, reloadInterval);
    }