Reading Characters from a ByteBuffer

[Dan0100]

Hi everyone,

I have a ByteBuffer with some information in it. At some point it needs to read a set of UTF characters. I have the length of these characters stored in a Short just before the bytes of the characters.

Currently my code looks like:

int len = byteBuffer.getShort();
String msg = decoder.decode(byteBuffer).toString();

This works fine but it reads the whole of the remainder of the byteBuffer. I need it to read only the the number of bytes specified by len.

On a side note is this the most efficient way to check I have enough data before I read it? (it works by storing the length as a short, reading that number of bytes and checking if there are any more bytes left over):

protected void readData(ByteBuffer readBuffer) throws IOException {
         if (readBuffer.limit() > 2) {
            int pos = readBuffer.position();
            int len = readBuffer.getShort();

            if (readBuffer.remaining() >= len) {
                
                readCommand(readBuffer);

                if (readBuffer.remaining() != 0) {
                    readData(readBuffer);
                } else {
                    readBuffer.clear();
                }

            } else {
                readBuffer.position(pos);
            }
        }
}

Thanks for your help and reading,
Dan

[Norm]

Does this method: decoder.decode() have an overloaded version that takes a length?

[Dan0100]

My fix:

public String readString(ByteBuffer data) throws CharacterCodingException {
        int len = data.getShort();
        int originalLimit = data.limit();

        data.limit(data.position() + len);
        String msg = Main.decoder.decode(data).toString();
        data.limit(originalLimit);

        return msg;
}