virtual Status SetAttrFloat(const char* attr_name, float value) = 0;
  virtual Status SetAttrBool(const char* attr_name, bool value) = 0;
  virtual Status SetAttrType(const char* attr_name, DataType value) = 0;
  virtual Status SetAttrShape(const char* attr_name, const int64_t* dims,
                              const int num_dims) = 0;
  virtual Status SetAttrShape(const char* attr_name,

Status SetAttrString(AbstractOperation*, const char* attr_name,
                     const char* data, size_t length, ForwardOperation*);
Status SetAttrInt(AbstractOperation*, const char* attr_name, int64_t value,
                  ForwardOperation*);
Status SetAttrFloat(AbstractOperation*, const char* attr_name, float value,
                    ForwardOperation*);
Status SetAttrBool(AbstractOperation*, const char* attr_name, bool value,

                 int* num_retvals) override;
  Status SetAttrString(const char* attr_name, const char* data,
                       size_t length) override;
  Status SetAttrInt(const char* attr_name, int64_t value) override;
  Status SetAttrFloat(const char* attr_name, float value) override;
  Status SetAttrBool(const char* attr_name, bool value) override;
  Status SetAttrType(const char* attr_name, DataType value) override;

   */
  @Override
  @CheckForNull
  protected final char[] escape(char c) {
    if (c < replacementsLength) {
      char[] chars = replacements[c];
      if (chars != null) {
        return chars;
      }
    }
    if (c >= safeMin && c <= safeMax) {
      return null;
    }
    return escapeUnsafe(c);
  }

  /**
   * Escapes a {@code char} value that has no direct explicit value in the replacement array and

          private final char[] unknown = new char[] {'?'};

          @Override
          protected char[] escapeUnsafe(char c) {
            return unknown;
          }
        };
    EscaperAsserts.assertBasic(replacingEscaper);

    // Replacements are applied first regardless of whether the character is in
    // the safe range or not ('&' is a safe char while '\t' and '\n' are not).
    assertEquals(

     */
    public static String toHexString ( int val, int size ) {
        char[] c = new char[size];
        toHexChars(val, c, 0, size);
        return new String(c);
    }


    /**
     * @param val
     * @param size
     * @return hex string
     */
    public static String toHexString ( long val, int size ) {
        char[] c = new char[size];
        toHexChars(val, c, 0, size);
        return new String(c);

          private final char[] unknown = new char[] {'?'};

          @Override
          protected char[] escapeUnsafe(int c) {
            return unknown;
          }
        };
    EscaperAsserts.assertBasic(replacingEscaper);

    // Replacements are applied first regardless of whether the character is in
    // the safe range or not ('&' is a safe char while '\t' and '\n' are not).
    assertEquals(

                          const char* name = "scalar");

TF_Operation* ScalarConst(double v, TF_Graph* graph, TF_Status* s,
                          const char* name = "scalar");

TF_Operation* ScalarConst(float v, TF_Graph* graph, TF_Status* s,
                          const char* name = "scalar");

TF_Operation* Add(TF_Operation* l, TF_Operation* r, TF_Graph* graph,
                  TF_Status* s, const char* name = "add");

      }
    }
  }

  private static String mikeRepeat(String string, int count) {
    final 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) {

      return insertionOrder;
    }
  }

  public static class SampleChars extends SampleElements<Character> {
    public SampleChars() {
      super((char) 0, (char) 1, (char) 2, (char) 3, (char) 4);
    }
  }