### Question:
RLP { public static byte[] encodeLength(int length, int offset) { if (length < SIZE_THRESHOLD) { byte firstByte = (byte) (length + offset); return new byte[] {firstByte}; } else { byte[] binaryLength; if (length > 0xFF) { binaryLength = intToBytesNoLeadZeroes(length); } else { binaryLength = new byte[] {(byte) length}; } byte firstByte = (byte) (binaryLength.length + offset + SIZE_THRESHOLD - 1); return concatenate(new byte[] {firstByte}, binaryLength); } }  static int decodeInt(byte[] data, int index); static BigInteger decodeBigInteger(byte[] data, int index); static RLPList decode2(byte[] msgData); static RLPElement decode2OneItem(byte[] msgData, int startPos); static DecodeResult decode(byte[] data, int pos); static byte[] encode(Object input); static byte[] encodeLength(int length, int offset); static byte[] encodeByte(byte singleByte); static byte[] encodeShort(short singleShort); static byte[] encodeInt(int singleInt); static byte[] encodeLong(long l); static byte[] encodeString(String srcString); static byte[] encodeBigInteger(BigInteger srcBigInteger); static byte[] encodeElement(byte[] srcData); static int calcElementPrefixSize(byte[] srcData); static byte[] encodeListHeader(int size); static byte[] encodeLongElementHeader(int length); static byte[] encodeList(byte[]... elements);  }### Answer:
@Test public void testEncodeLength() { int length = 1; int offset = 128; byte[] encodedLength = encodeLength(length, offset); String expected = "81"; assertEquals(expected, Hex.toHexString(encodedLength)); length = 56; offset = 192; encodedLength = encodeLength(length, offset); expected = "f838"; assertEquals(expected, Hex.toHexString(encodedLength)); }