@GwtIncompatible
@ElementTypesAreNonnullByDefault
public class CycleDetectingLockFactory {

  /**
   * Encapsulates the action to be taken when a potential deadlock is encountered. Clients can use
   * one of the predefined {@link Policies} or specify a custom implementation. Implementations must
   * be thread-safe.
   *
   * @since 13.0
   */
  public interface Policy {

    /**

   *
   * @param url the URL to read from
   * @param charset the charset used to decode the input stream; see {@link Charsets} for helpful
   *     predefined constants
   * @return a string containing all the characters from the URL
   * @throws IOException if an I/O error occurs.
   */
  public static String toString(URL url, Charset charset) throws IOException {

   *
   * @param file the file to read from
   * @param charset the charset used to decode the input stream; see {@link StandardCharsets} for
   *     helpful predefined constants
   * @return the buffered reader
   */
  public static BufferedReader newReader(File file, Charset charset) throws FileNotFoundException {
    checkNotNull(file);
    checkNotNull(charset);

 * Content-Type} header and as such has no support for header-specific considerations such as line
 * folding and comments.
 *
 * <p>For media types that take a charset the predefined constants default to UTF-8 and have a
 * "_UTF_8" suffix. To get a version without a character set, use {@link #withoutParameters}.
 *
 * @since 12.0
 * @author Gregory Kick
 */
@GwtCompatible
@Immutable