public void testExpiringMemoizedSupplierThreadSafe() throws Throwable {
    Function<Supplier<Boolean>, Supplier<Boolean>> memoizer =
        new Function<Supplier<Boolean>, Supplier<Boolean>>() {
          @Override
          public Supplier<Boolean> apply(Supplier<Boolean> supplier) {
            return Suppliers.memoizeWithExpiration(supplier, Long.MAX_VALUE, NANOSECONDS);
          }
        };
    testSupplierThreadSafe(memoizer);

package com.google.common.hash;

import com.google.common.base.Supplier;
import java.util.concurrent.atomic.AtomicLong;

/**
 * Source of {@link LongAddable} objects that deals with GWT, Unsafe, and all that.
 *
 * @author Louis Wasserman
 */
final class LongAddables {
  private static final Supplier<LongAddable> SUPPLIER;

  static {
    Supplier<LongAddable> supplier;
    try {

   * obtained from the passed supplier.
   *
   * @param stripes the minimum number of stripes (locks) required
   * @param supplier a {@code Supplier<L>} object to obtain locks from
   * @return a new {@code Striped<L>}
   * @since 33.5.0
   */
  public static <L> Striped<L> custom(int stripes, Supplier<L> supplier) {
    return new CompactStriped<>(stripes, supplier);
  }

  /**

import com.google.common.base.Supplier;
import com.google.common.collect.ForwardingSet;
import java.util.Set;

/**
 * A subclass of `ForwardingSet` that throws `IllegalStateException` on invocation of any method
 * (except `hashCode` and `equals`) if the provided `Supplier` returns false.
 */
final class InvalidatableSet<E> extends ForwardingSet<E> {
  private final Supplier<Boolean> validator;
  private final Set<E> delegate;

     * @param supplier The function to execute and cache the result
     * @return The result from the supplier (either fresh or cached)
     * @throws RuntimeException Any exception thrown by the supplier will be cached and re-thrown on subsequent calls
     */
    <REQ extends Request<?>, REP extends Result<REQ>> REP request(REQ req, Function<REQ, REP> supplier);

    /**

      Supplier<T> supplier) {
    return new SupplierFunction<>(supplier);
  }

  /**
   * @see Functions#forSupplier
   */
  private static final class SupplierFunction<
          F extends @Nullable Object, T extends @Nullable Object>
      implements Function<F, T>, Serializable {

    private final Supplier<T> supplier;

    private SupplierFunction(Supplier<T> supplier) {

  /**
   * Returns a cache loader based on an <i>existing</i> supplier instance. Note that there's no need
   * to create a <i>new</i> supplier just to pass it in here; just subclass {@code CacheLoader} and
   * implement {@link #load load} instead.
   *
   * <p>The returned object is serializable if {@code supplier} is serializable.
   *
   * @param supplier the supplier to be used for loading values; must never return {@code null}

    @Override
    public void debug(Throwable error) {
        logger.debug("", error);
    }

    @Override
    public void debug(Supplier<String> content) {
        if (isDebugEnabled()) {
            logger.debug(content.get());
        }
    }

    @Override
    public void debug(Supplier<String> content, Throwable error) {
        if (isDebugEnabled()) {
            logger.debug(content.get(), error);
        }
    }

        @SuppressWarnings("unchecked")
        Supplier<String> supplier = mock(Supplier.class);
        when(supplier.get()).thenThrow(new RuntimeException(new SmbUnsupportedOperationException("boom")));

        // Act & Assert: the exception is propagated and interaction recorded once
        RuntimeException thrown = assertThrows(RuntimeException.class, supplier::get);

            return defaultLocaleSupplier.get();
        }
        return Locale.ENGLISH;
    }

    /**
     * Sets the default locale supplier.
     *
     * @param localeSupplier
     *            the supplier for the default locale
     */
    public static void setDefault(final Supplier<Locale> localeSupplier) {
        defaultLocaleSupplier = localeSupplier;
    }