### Question:
ByteUtils { public static byte[] escape(byte[] in) { int escapeCount = 0; for (byte value : in) { if (value == 0x00 || value == 0x01) { escapeCount++; } } if (escapeCount == 0) return in; byte[] ret = new byte[escapeCount + in.length]; int index = 0; for (byte b : in) { switch (b) { case 0x00: ret[index++] = 0x01; ret[index++] = 0x01; break; case 0x01: ret[index++] = 0x01; ret[index++] = 0x02; break; default: ret[index++] = b; } } return ret; }  static byte[] escape(byte[] in); static byte[] unescape(byte[] in); static byte[][] split(byte[] data); static byte[][] split(byte[] data, int dataOffset, int len); static byte[] concat(byte[]... fields);  }### Answer:
@Test public void testEscape() { byte[] bytes = {0x00, 0x01}; byte[] escaped = ByteUtils.escape(bytes); assertArrayEquals(bytes, ByteUtils.unescape(escaped)); byte[] notEscaped = {0x02, 0x02, 0x02}; assertArrayEquals(notEscaped, ByteUtils.unescape(notEscaped)); }