public Escaper build() {
      return new ArrayBasedCharEscaper(replacementMap, safeMin, safeMax) {
        private final char @Nullable [] replacementChars =
            unsafeReplacement != null ? unsafeReplacement.toCharArray() : null;

        @Override
        protected char @Nullable [] escapeUnsafe(char c) {
          return replacementChars;
        }
      };
    }
  }

  /**

    }
  }

  public void testUtf8() {
    char[] charsA = new char[128];
    char[] charsB = new char[128];

    for (int i = 0; i < charsA.length; i++) {
      if (i < 100) {
        charsA[i] = 'a';
        charsB[i] = 'a';
      } else {
        // Both two-byte characters, but must be different
        charsA[i] = (char) (0x0180 + i);
        charsB[i] = (char) (0x0280 + i);
      }
    }

  // original character value.
  @VisibleForTesting
  static char[][] createReplacementArray(Map<Character, String> map) {
    checkNotNull(map); // GWT specific check (do not optimize)
    if (map.isEmpty()) {
      return EMPTY_REPLACEMENT_ARRAY;
    }
    char max = max(map.keySet());
    char[][] replacements = new char[max + 1][];
    for (Character c : map.keySet()) {

  private final char innerNodeCode;

  /** The character used for a leaf node in the trie encoding */
  private final char leafNodeCode;

  PublicSuffixType(char innerNodeCode, char leafNodeCode) {
    this.innerNodeCode = innerNodeCode;
    this.leafNodeCode = leafNodeCode;
  }

  char getLeafNodeCode() {
    return leafNodeCode;
  }

  char getInnerNodeCode() {
    return innerNodeCode;

            }
            count++;
        }

        return value;
    }

    static final char[] HEXCHARS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

    private static String bin_to_hex(int value, final int length) {
        final char[] arr = new char[length];
        int ai = arr.length;
        while (ai-- > 0) {
            arr[ai] = HEXCHARS[value & 0xF];

      }
    }
  }

  private static String mikeRepeat(String string, int count) {
    int len = string.length();
    char[] strCopy = new char[len * Integer.highestOneBit(count)];
    string.getChars(0, len, strCopy, 0);

    char[] array = new char[len * count];

    int strCopyLen = len;
    int pos = 0;
    while (count != 0) {
      if ((count & 1) != 0) {

        if (length == 0) {
            return;
        }

        final int s = length % 16;
        final int r = s == 0 ? length / 16 : length / 16 + 1;
        final char[] c = new char[r * (74 + NL_LENGTH)];
        final char[] d = new char[16];
        int i;
        int si = 0;
        int ci = 0;

        do {
            toHexChars(si, c, ci, 5);
            ci += 5;
            c[ci] = ':';

      assertThat(expected.message)
        .isEqualTo("Unexpected char 0xe9 at 1 in header name: héader1")
    }
  }

  @Test fun builderRejectsUnicodeInHeaderValue() {
    assertFailsWith<IllegalArgumentException> {
      Headers.Builder().add("header1", "valué1")
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("Unexpected char 0xe9 at 4 in header1 value: valué1")
    }
  }

     * @return the hexadecimal string representation
     */
    public static String bin_to_hex(int value, final int length) {
        final char[] arr = new char[length];
        int ai = arr.length;
        while (ai-- > 0) {
            arr[ai] = HEXCHARS[value & 0xF];
            value >>>= 4;
        }
        return new String(arr);
    }

    private static byte B(final int i) {

        new UnicodeEscaper() {
          // Canonical escaper method that only escapes lower case ASCII letters.
          @Override
          protected char @Nullable [] escape(int cp) {
            return ('a' <= cp && cp <= 'z') ? new char[] {Character.toUpperCase((char) cp)} : null;
          }

          // Inefficient implementation that defines all letters as escapable.
          @Override