public void testIsWellFormed_4BytesSamples() {
    // Valid 4 byte.
    assertWellFormed(0xF0, 0xA4, 0xAD, 0xA2);
    // Bad trailing bytes
    assertNotWellFormed(0xF0, 0xA4, 0xAD, 0x7F);
    assertNotWellFormed(0xF0, 0xA4, 0xAD, 0xC0);
    // Special cases for byte2
    assertNotWellFormed(0xF0, 0x8F, 0xAD, 0xA2);
    assertNotWellFormed(0xF4, 0x90, 0xAD, 0xA2);
  }

  /** Tests some hard-coded test cases. */

0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44,...

     */
    public static void appendHex(final StringBuilder buf, final int i) {
        buf.append(Integer.toHexString(i >> 24 & 0xff));
        buf.append(Integer.toHexString(i >> 16 & 0xff));
        buf.append(Integer.toHexString(i >> 8 & 0xff));
        buf.append(Integer.toHexString(i & 0xff));
    }

    /**
     * Converts an underscore-separated string to camel case.
     * <p>
     * Usage example:

	LDAXRB (R19), R16                          // 70fe5f08
	LDAXRH (R5), R8                            // a8fc5f48
	//TODO LDNP 0xcc(RSP), ZR, R12             // ecff5928
	//TODO LDNP 0x40(R28), R9, R5              // 852744a8
	//TODO LDPSW -0xd0(R2), R0, R12            // 4c00e668
	//TODO LDPSW 0x5c(R4), R8, R5              // 85a0cb69
	//TODO LDPSW 0x6c(R12), R2, R27            // 9b894d69

          val b = source.readByte() and 0xff
          when {
            b == 0x80 -> {
              // 10000000
              throw IOException("index == 0")
            }

            b and 0x80 == 0x80 -> {
              // 1NNNNNNN
              val index = readInt(b, PREFIX_7_BITS)
              readIndexedHeader(index - 1)
            }

            b == 0x40 -> {
              // 01000000

		0x49, 0xd5, 0xe3, 0x02, 0x04, 0x00, 0x00, 0xff,
		0xff, 0x50, 0x4b, 0x07, 0x08, 0xc0, 0xd7, 0xed,
		0xc3, 0x20, 0x00, 0x00, 0x00, 0x1a, 0x00, 0x00,
		0x00, 0x50, 0x4b, 0x01, 0x02, 0x14, 0x00, 0x14,
		0x00, 0x08, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
		0x00, 0xc0, 0xd7, 0xed, 0xc3, 0x20, 0x00, 0x00,
		0x00, 0x1a, 0x00, 0x00, 0x00, 0x0b, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

  const val FLAG_END_HEADERS = 0x4 // Used for headers and continuation.
  const val FLAG_END_PUSH_PROMISE = 0x4
  const val FLAG_PADDED = 0x8 // Used for headers and data.
  const val FLAG_PRIORITY = 0x20 // Used for headers.
  const val FLAG_COMPRESSED = 0x20 // Used for data.

  /** Lookup table for valid frame types. */
  private val FRAME_NAMES =
    arrayOf(
      "DATA",
      "HEADERS",
      "PRIORITY",
      "RST_STREAM",

	MOVL	ptr+0(FP), AX
	TESTL	$7, AX
	JZ	2(PC)
	MOVL	0, AX // crash with nil ptr deref
	LEAL	ret_lo+4(FP), BX
	// MOVQ (%EAX), %MM0
	BYTE $0x0f; BYTE $0x6f; BYTE $0x00
	// MOVQ %MM0, 0(%EBX)
	BYTE $0x0f; BYTE $0x7f; BYTE $0x03
	// EMMS
	BYTE $0x0F; BYTE $0x77
	RET

              new byte[] {(byte) 0xcd, (byte) 0xab, (byte) 0x00, (byte) 0x00},
              0x0000abcd,
              null,
              "cdab0000"),
          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x00,
                (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00
              },
              0x00abcdef,
              0x0000000000abcdefL,

        new byte[] {
          0x01, (byte) 0xc0, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x14, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x04, 0x00,
          0x00, 0x00, 0x00, 0x14,
          0x00, 0x00, 0x00, 0x18,
          0x28, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x02, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00