Barklund.org

protected CoderResult decodeLoop(ByteBuffer in, CharBuffer out) {
	int inPos = in.position();
	try {
		while (in.hasRemaining()) {
			char c;
			byte b1 = in.get();
			int highNibble = (b1 >> 4) & 0xF;
 
			switch (highNibble) {
			case 0:
			case 1:
			case 2:
			case 3:
			case 4:
			case 5:
			case 6:
			case 7:
				if (out.remaining() < 1)
					return CoderResult.OVERFLOW;
				out.put((char) b1);
				inPos = in.position();
				break;
 
			case 0xC:
			case 0xD:
				byte b2;
				if (in.remaining() < 1)
					return CoderResult.UNDERFLOW;
				if (out.remaining() < 1)
					return CoderResult.OVERFLOW;
				if (!isContinuation(b2 = in.get())) {
					// put second char back by rewinding, putting and re-rewinding
					in.position(in.position()-1);
					in.put(b2);
					in.position(in.position()-1);
					// update last read legal position
					inPos = in.position();
					// append byte directly used
					out.append((char) (b1 & 0xFF));
					// break switch
					break;
				}
				c = (char) (((b1 & 0x1F) << 6) | (b2 & 0x3F));
				// check that we had the shortest encoding
				if (c <= 0x7F)
					return CoderResult.malformedForLength(2);
				out.put(c);
				inPos = in.position();
				break;
 
			case 0xE:
				byte b3;
				if (in.remaining() < 2)
					return CoderResult.UNDERFLOW;
				if (out.remaining() < 1)
					return CoderResult.OVERFLOW;
				if (!isContinuation(b2 = in.get())) {
					// put second char back by rewinding, putting and re-rewinding
					in.position(in.position()-1);
					in.put(b2);
					in.position(in.position()-1);
					// update last read legal position
					inPos = in.position();
					// append byte directly used
					out.append((char) (b1 & 0xFF));
					// break switch
					break;
				}
				if (!isContinuation(b3 = in.get())) {
					// put third char back by rewinding, putting and re-rewinding
					in.position(in.position()-1);
					in.put(b3);
					in.position(in.position()-1);
					// update last read legal position
					inPos = in.position();
					// append first and second byte directly used
					out.append((char) (b1 & 0xFF));
					out.append((char) (b2 & 0xFF));
					// break switch
					break;
				}
				c = (char) (((b1 & 0x0F) << 12) | ((b2 & 0x3F) << 6) | (b3 & 0x3F));
				// check that we had the shortest encoding
				if (c <= 0x7FF)
					return CoderResult.malformedForLength(3);
				out.put(c);
				inPos = in.position();
				break;
 
			default:
				// parse as latin 1
				out.append((char) (b1 & 0xFF));
				inPos = in.position();
				break;
			}
		}
 
		return CoderResult.UNDERFLOW;
	} finally {
		// In case we did a get(), then encountered an error, reset the
		// position to before the error.  If there was no error, this
		// will benignly reset the position to the value it already has.
		in.position(inPos);
	}
}