this.supplier = supplier;
    }
  }

  @Param private CollectionType source;

  enum Operation {
    FIND_FIRST {
      @Override
      Object operate(Stream<?> stream) {
        return stream.findFirst();
      }
    },
    STREAMS_ONLY_ELEMENT {
      @Override
      Object operate(Stream<?> stream) {
        try {
          return stream.collect(onlyElement());

     *
     * @param error the error that caused this log
     */
    void debug(Throwable error);

    void debug(Supplier<String> content);

    void debug(Supplier<String> content, Throwable error);

    /**
     * {@return true if the <b>info</b> error level is enabled}
     */
    boolean isInfoEnabled();

    /**

    @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);
        }
    }

    protected StringBuilder append(final StringBuilder buf, final String key, final Supplier<Object> supplier) {
        final StringBuilder tempBuf = new StringBuilder();
        tempBuf.append('"').append(key).append("\":");
        try {
            final Object value = supplier.get();
            if (value == null) {
                tempBuf.append("null");

    @Nullable Object get() throws Throwable;
  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(
      Class<T> expectedThrowable, ThrowingSupplier supplier) {
    return doAssertThrows(expectedThrowable, supplier, /* userPassedSupplier= */ true);
  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(
      Class<T> expectedThrowable, ThrowingRunnable runnable) {

    @Nullable Object get() throws Throwable;
  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(
      Class<T> expectedThrowable, ThrowingSupplier supplier) {
    return doAssertThrows(expectedThrowable, supplier, /* userPassedSupplier= */ true);
  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(
      Class<T> expectedThrowable, ThrowingRunnable runnable) {

                }
            }
            return model;
        }

        public Model computeIfAbsent(Supplier<Model> supplier) {
            if (!set) {
                synchronized (this) {
                    if (!set) {
                        this.set = true;
                        this.model = supplier.get();
                        this.notifyAll();
                    }
                }
            }

    }


private
fun hasConstructorAttribute(constructorsSupplier: Supplier<MutableList<KmConstructor>>, jvmSignature: String, predicate: AttributePredicate) =
    constructorsSupplier.get().firstOrNull { c -> jvmSignature == c.signature?.toString() }?.let { predicate.match(it) } ?: false


private
fun hasFunctionAttribute(functionsSupplier: Supplier<MutableList<KmFunction>>, jvmSignature: String, predicate: AttributePredicate) =

  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);

  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);