*
   * This returns null if:
   *
   *  * The stream is exhausted.
   *  * We've read all of the bytes of an object whose length is known.
   *  * We've reached the [DerHeader.TAG_END_OF_CONTENTS] of an object whose length is unknown.
   */
  fun peekHeader(): DerHeader? {
    var result = peekedHeader

    if (result == null) {
      result = readHeader()

@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface SuccessorsFunction<N> {

  /**
   * Returns all nodes in this graph adjacent to {@code node} which can be reached by traversing
   * {@code node}'s outgoing edges in the direction (if any) of the edge.
   *
   * <p>This is <i>not</i> the same as "all nodes reachable from {@code node} by following outgoing

   * linefeed ({@code "\r\n"}).
   *
   * @return a {@code String} containing the contents of the line, not including any
   *     line-termination characters, or {@code null} if the end of the stream has been reached.
   * @throws IOException if an I/O error occurs
   */
  @CanIgnoreReturnValue // to skip a line
  public @Nullable String readLine() throws IOException {
    while (lines.peek() == null) {

     *
     * @param reader
     *            the {@link BufferedReader} (must not be {@literal null})
     * @return a line of text, or {@literal null} if the end of the stream has been reached
     * @see BufferedReader#readLine()
     */
    public static String readLine(final BufferedReader reader) {
        assertArgumentNotNull("reader", reader);

        try {

        if (verifySignature(toVerify, signingCert, result.size - 1)) {
          i.remove()
          result.add(signingCert)
          continue@followIssuerChain
        }
      }

      // We've reached the end of the chain. If any cert in the chain is trusted, we're done.
      if (foundTrustedCertificate) {
        return result
      }

      // The last link isn't trusted. Fail.

import java.util.Iterator;
import java.util.Set;

/**
 * A {@link Set} implementation that stores its elements in a {@link LruHashMap}.
 * <p>
 * This set has a fixed maximum capacity. When the capacity is reached and a new element is added,
 * the least recently used element is removed.
 * </p>
 * @author shinsuke
 * @param <E> the type of elements maintained by this set
 */

@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface PredecessorsFunction<N> {

  /**
   * Returns all nodes in this graph adjacent to {@code node} which can be reached by traversing
   * {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>Some algorithms that operate on a {@code PredecessorsFunction} may produce undesired results

@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface SuccessorsFunction<N> {

  /**
   * Returns all nodes in this graph adjacent to {@code node} which can be reached by traversing
   * {@code node}'s outgoing edges in the direction (if any) of the edge.
   *
   * <p>This is <i>not</i> the same as "all nodes reachable from {@code node} by following outgoing

   *     which case the input string is always returned.
   * @param padChar the character to insert at the beginning of the result until the minimum length
   *     is reached
   * @return the padded string
   */
  public static String padStart(String string, int minLength, char padChar) {
    checkNotNull(string); // eager for GWT.
    if (string.length() >= minLength) {
      return string;

        break;
      }
    }
    return processor.getResult();
  }

  /**
   * Reads and discards data from the given {@code Readable} until the end of the stream is reached.
   * Returns the total number of chars read. Does not close the stream.
   *
   * @since 20.0
   */
  @CanIgnoreReturnValue
  public static long exhaust(Readable readable) throws IOException {