private final Map<Character, String> replacementMap = new HashMap<>();
    private char safeMin = Character.MIN_VALUE;
    private char safeMax = Character.MAX_VALUE;
    @CheckForNull private String unsafeReplacement = null;

    // The constructor is exposed via the builder() method above.
    private Builder() {}

    /**
     * Sets the safe range of characters for the escaper. Characters in this range that have no

  }

  /**
   * Returns the escaped form of the given character, or {@code null} if this character does not
   * need to be escaped. If an empty array is returned, this effectively strips the input character
   * from the resulting text.
   *
   * <p>If the character does not need to be escaped, this method should return {@code null}, rather
   * than a one-character array containing the character itself. This enables the escaping algorithm

 *       doing something and finally closing the writer that was opened.
 * </ul>
 *
 * <p>Any {@link ByteSink} may be viewed as a {@code CharSink} with a specific {@linkplain Charset
 * character encoding} using {@link ByteSink#asCharSink(Charset)}. Characters written to the
 * resulting {@code CharSink} will written to the {@code ByteSink} as encoded bytes.
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible

  private boolean sawReturn;

  /**
   * Process additional characters from the stream. When a line separator is found the contents of
   * the line and the line separator itself are passed to the abstract {@link #handleLine} method.
   *
   * @param cbuf the character buffer to process
   * @param off the offset into the buffer
   * @param len the number of characters to process
   * @throws IOException if an I/O error occurs

    assertEquals(safeInput, surrogateEscaper.escape(safeInput));

    // A surrogate pair defining a code point outside the safe range (but both
    // of the surrogate characters lie within the safe range). It is important
    // not to accidentally treat this as a sequence of safe characters.
    String unsafeInput = "\uDBFF\uDFFF"; // 0x10FFFF
    assertEquals("X", surrogateEscaper.escape(unsafeInput));
  }

          TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Permutations of one and two byte characters
          3
              * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS
              * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS
              * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Four byte characters
          FOUR_BYTE_ROUNDTRIPPABLE_CHARACTERS;

  /**
   * Substitute: A character that may be substituted for a character which is determined to be
   * invalid or in error.
   *
   * @since 8.0
   */
  public static final byte SUB = 26;

  /**
   * Escape: A control character intended to provide code extension (supplementary characters) in
   * general information interchange. The Escape character itself is a prefix affecting the

   *       the same.
   *   <li>The special characters ".", "-", "*", and "_" remain the same.
   *   <li>The space character " " is converted into a plus sign "+".
   *   <li>All other characters are converted into one or more bytes using UTF-8 encoding and each
   *       byte is then represented by the 3-character string "%XY", where "XY" is the two-digit,
   *       uppercase, hexadecimal representation of the byte value.
   * </ul>
   *

   *
   * @param replacementMap a map of characters to their escaped representations
   * @param safeMin the lowest character value in the safe range
   * @param safeMax the highest character value in the safe range
   * @param unsafeReplacement the default replacement for unsafe characters or null if no default
   *     replacement is required
   */
  protected ArrayBasedUnicodeEscaper(
      Map<Character, String> replacementMap,
      int safeMin,

    return requireNonNull(DEST_TL.get());
  }

  /**
   * A thread-local destination buffer to keep us from creating new buffers. The starting size is
   * 1024 characters. If we grow past this we don't put it back in the threadlocal, we just keep
   * going and grow as needed.
   */
  private static final ThreadLocal<char[]> DEST_TL =
      new ThreadLocal<char[]>() {
        @Override