com.davidehrmann.vcdiff

Interface VCDiffStreamingDecoder

All Known Implementing Classes:

VCDiffStreamingDecoderImpl

public interface VCDiffStreamingDecoder

Method Summary

Modifier and Type	Method and Description
void	decodeChunk(byte[] data, int offset, int length, OutputStream out) Deprecated. use decodeChunk(ByteBuffer, OutputStream) Accepts "data[offset,offset+length-1]" as additional data received in the compressed stream. If any chunks of data can be fully decoded, they are appended to out.
void	decodeChunk(byte[] data, OutputStream out) Convenience method equivalent to decodeChunk(data, 0, data.length, out)
void	decodeChunk(ByteBuffer data, OutputStream out) Accepts "data[offset,offset+length-1]" as additional data received in the compressed stream.
void	finishDecoding() Finishes decoding after all data has been received.
void	setAllowVcdTarget(boolean allowVcdTarget) This interface must be called before startDecoding().
boolean	setMaximumTargetFileSize(long newMaximumTargetFileSize) Specifies the maximum allowable target file size.
boolean	setMaximumTargetWindowSize(int newMaximumTargetWindowSize) Specifies the maximum allowable target *window* size.
void	startDecoding(byte[] dictionary) Deprecated. use startDecoding(ByteBuffer)
void	startDecoding(ByteBuffer dictionary) Resets the dictionary to dictionary parameter and sets up the data structures for decoding.

Method Detail

startDecoding

@Deprecated
void startDecoding(byte[] dictionary)

Deprecated. use startDecoding(ByteBuffer)

startDecoding

void startDecoding(ByteBuffer dictionary)

Resets the dictionary to dictionary parameter and sets up the data structures for decoding. Note that the dictionary contents are not copied, and the call is responsible for ensuring that dictionary is not modified until finishDecoding is called.

Parameters:

dictionary - dictionary the decoder is initialized with

decodeChunk

@Deprecated
void decodeChunk(byte[] data,
                              int offset,
                              int length,
                              OutputStream out)
                       throws IOException

Deprecated. use decodeChunk(ByteBuffer, OutputStream) Accepts "data[offset,offset+length-1]" as additional data received in the compressed stream. If any chunks of data can be fully decoded, they are appended to out.

Parameters:

data - data to decoder

offset - offset in data to decode from

length - number of bytes in data to decide

out - OutputStream to write decoded data to

Throws:

IOException - if an error occurred decoding chunk or writing the decoded chunk to out

decodeChunk

void decodeChunk(ByteBuffer data,
                 OutputStream out)
          throws IOException

Accepts "data[offset,offset+length-1]" as additional data received in the compressed stream. If any chunks of data can be fully decoded, they are appended to out.

Parameters:

data - data to decoder

out - OutputStream to write decoded data to

Throws:

IOException - if an error occurred decoding chunk or writing the decoded chunk to out

decodeChunk

void decodeChunk(byte[] data,
                 OutputStream out)
          throws IOException

Convenience method equivalent to decodeChunk(data, 0, data.length, out)

Parameters:

data - data to decoder

out - OutputStream to write decoded data to

Throws:

IOException - if an error occurred decoding chunk or writing the decoded chunk to out

finishDecoding

void finishDecoding()
             throws IOException

Finishes decoding after all data has been received. finishDecoding() must be called for the current target before startDecoding() can be called for a different target.

Throws:

IOException - if there's an error finishing decoding

setMaximumTargetFileSize

boolean setMaximumTargetFileSize(long newMaximumTargetFileSize)

Specifies the maximum allowable target file size. If the decoder encounters a delta file that would cause it to create a target file larger than this limit, it will throw an IOException and stop decoding. If the decoder is applied to delta files whose sizes vary greatly and whose contents can be trusted, then a value larger than the the default value (64 MB) can be specified to allow for maximum flexibility. On the other hand, if the input data is known never to exceed a particular size, and/or the input data may be maliciously constructed, a lower value can be supplied in order to guard against running out of memory or swapping to disk while decoding an extremely large target file. The argument must be between 0 and INT32_MAX (2G); if it is within these bounds, the function will set the limit and return true. Otherwise, the function will return false and will not change the limit. Setting the limit to 0 will cause all decode operations of non-empty target files to fail.

Parameters:

newMaximumTargetFileSize - maximum size allowed output size

Returns:

whether or not the maximum target file size was changed successfully

setMaximumTargetWindowSize

boolean setMaximumTargetWindowSize(int newMaximumTargetWindowSize)

Specifies the maximum allowable target *window* size. (A target file is composed of zero or more target windows.) If the decoder encounters a delta window that would cause it to create a target window larger than this limit, it will log an error and stop decoding.

Parameters:

newMaximumTargetWindowSize - maximum size of target windows allowed

Returns:

whether or not the maximum target window size was changed successfully

setAllowVcdTarget

void setAllowVcdTarget(boolean allowVcdTarget)

This interface must be called before startDecoding(). If its argument is true, then the VCD_TARGET flag can be specified to allow the source segment to be chosen from the previously-decoded target data. (This is the default behavior.) If it is false, then specifying the VCD_TARGET flag is considered an error, and the decoder does not need to keep in memory any decoded target data prior to the current window.

Parameters:

allowVcdTarget - whether or not to allow the decoder to use decoded VCD data as a target