lejos.charset
Interface CharsetDecoder

All Known Implementing Classes:

Latin1Decoder, UTF8Decoder

public interface CharsetDecoder

Method Summary

int	decode(byte[] buf, int offset, int limit) Calculates a Unicode codepoint from the bytes in the buffer.
int	estimateByteCount(byte[] buf, int offset, int limit) Calculates the number of bytes that are needed to decode a full Unicode codepoint at the given position in the byte array.
int	getMaxCharLength()

Method Detail

getMaxCharLength

int getMaxCharLength()

decode

int decode(byte[] buf,
           int offset,
           int limit)

Calculates a Unicode codepoint from the bytes in the buffer. If the bytes in the buffer cannot be decoded, because they are malformed or because there is not enough data, then the '?' character should be returned.

Parameters:

buf - the array of bytes

offset - the index of the first byte to be read

limit - the index after the last byte that is to be read

Returns:

the Unicode codepoint or '?'

estimateByteCount

int estimateByteCount(byte[] buf,
                      int offset,
                      int limit)

Calculates the number of bytes that are needed to decode a full Unicode codepoint at the given position in the byte array. The function must handle three cases: a) the given array does contain the full encoding of a Unicode codepoint b) the given data is too short to be the encoding of a Unicode codepoint c) the given data is malformed In cases a) and c), the function must return the number of bytes that must be skipped after the decoding of the character. In case b), the function should return an estimation of the number of bytes needed to decode the next Unicode codepoint. Yet, this must not be an overestimation. In case b), the return value should be at least (limit - offset + 1).

Parameters:

buf - the array of bytes

offset - the index of the first byte to be read

limit - the index after the last byte that is to be read

Returns:

the estimated number of bytes