*
   * @param key the non-null key whose value should be loaded
   * @param oldValue the non-null old value corresponding to {@code key}
   * @return the future new value associated with {@code key}; <b>must not be null, must not return
   *     null</b>
   * @throws Exception if unable to reload the result
   * @throws InterruptedException if this method is interrupted. {@code InterruptedException} is

 * method equivalent to {@link java.util.concurrent.locks.ReentrantLock#hasQueuedThread(Thread)}. If
 * the {@link #callAndAssertWaits} method is ever called in a test, the lock-like object must have a
 * method equivalent to {@link
 * java.util.concurrent.locks.ReentrantLock#hasWaiters(java.util.concurrent.locks.Condition)},

   * unequivocally demonstrate that funneling cannot be occurring. This is done bit-by-bit. For each
   * input bit(i) and output bit(j), two pairs of keys must be found with all bits identical except
   * bit(i). One pair must differ in output bit(j), and one pair must not. This proves that input
   * bit(i) can alter output bit(j).
   */
  static void checkNoFunnels(HashFunction function) {
    Random rand = new Random(0);

    in Executable form must also be made available in Source Code form
    and that Source Code form must be distributed only under the terms
    of this License. You must include a copy of this License with every
    copy of the Source Code form of the Covered Software You distribute
    or otherwise make available. You must inform recipients of any such

   * @return the number of characters copied
   * @throws IOException if an I/O error occurs
   */
  @CanIgnoreReturnValue
  public static long copy(Readable from, Appendable to) throws IOException {
    // The most common case is that from is a Reader (like InputStreamReader or StringReader) so
    // take advantage of that.
    if (from instanceof Reader) {
      // optimize for common output types which are optimized to deal with char[]

 * This class contains a Kotlin implementation of the pseudocode specified by RFC 3492. It includes
 * direct translation of the pseudocode presented there.
 *
 * Partner this class with [UTS #46] to implement IDNA2008 [RFC 5890] like most browsers do.
 *
 * [RFC 3492]: https://datatracker.ietf.org/doc/html/rfc3492
 * [RFC 5890]: https://datatracker.ietf.org/doc/html/rfc5890
 * [UTS #46]: https://www.unicode.org/reports/tr46/
 */
object Punycode {

 *
 * <p>The <dfn>Dependency graph flattening</dfn> process in Maven reduces a complex,
 * multi-level dependency graph to a map of ordered lists that can be turned into classpaths.
 * During this process only the most relevant version of each artifact
 * (based on group ID and artifact ID) is retained, resolving conflicts and eliminating duplicates to ensure
 * that each dependency is included only once in the final build.</p>
 *

## Previous tools { #previous-tools }

### <a href="https://www.djangoproject.com/" class="external-link" target="_blank">Django</a> { #django }

It's the most popular Python framework and is widely trusted. It is used to build systems like Instagram.

 * and a fixed number of values. Each key must match the regex `[a-z0-9_-]{1,64}`. Values are byte
 * sequences, accessible as streams or files. Each value must be between `0` and `Int.MAX_VALUE`
 * bytes in length.
 *
 * The cache stores its data in a directory on the filesystem. This directory must be exclusive to

   * Character#isLetter(char) Java's definition}. If you only care to match letters of the Latin
   * alphabet, you can use {@code inRange('a', 'z').or(inRange('A', 'Z'))}.
   *
   * @deprecated Most letters are supplementary characters; see the class documentation.
   * @since 19.0 (since 1.0 as constant {@code JAVA_LETTER})
   */
  @Deprecated
  public static CharMatcher javaLetter() {