totalcross.util.zip

Class CompressedStream

java.lang.Object

totalcross.io.Stream

totalcross.util.zip.CompressedStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

GZipStream, ZipStream, ZLibStream

public abstract class CompressedStream
extends Stream

Base class for stream filters that perform data compression and decompression.

Since:

TotalCross 1.12

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.Object	compressedStream
static int	DEFLATE Used to create a stream that will be used for data compression.
static int	INFLATE Used to create a stream that will be used for data decompression.
protected int	mode

Fields inherited from class totalcross.io.Stream

skipBuffer

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	CompressedStream()
protected	CompressedStream(Stream stream, int mode) Creates a CompressedStream object that may be used to read compressed data from the given stream, or to write compressed data to the given stream.

Method Summary

Modifier and Type	Method and Description
void	close() Closes this stream WITHOUT closing the underlying stream, which must be explicitly closed by the user.
protected abstract java.lang.Object	createDeflate(Stream stream)
protected abstract java.lang.Object	createInflate(Stream stream)
protected void	finalize()
int	readBytes(byte[] buf, int start, int count) Attempts to read count bytes to the given byte array, starting from offset start. This method can be used only with CompressedStreams created in INFLATE mode, and should be used only for reading compressed data from the original stream, returning uncompressed data on the give byte array.
int	writeBytes(byte[] buf, int start, int count) Attempts to write count bytes from the given byte array, starting from offset start. This method can be used only with CompressedStreams created in DEFLATE mode, and should be used only for compressing the contents of the given byte array, and writing the compressed data to the original stream.

Methods inherited from class totalcross.io.Stream

asInputStream, asOutputStream, asStream, asStream, skipBytes, wrapInputStream, wrapInputStreamToStream, write, writeBytes, writeBytes, writeBytes

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

compressedStream

protected java.lang.Object compressedStream

mode

protected int mode

DEFLATE

public static final int DEFLATE

Used to create a stream that will be used for data compression. In this mode, you may NOT use the method readBytes.

See Also:

Constant Field Values

INFLATE

public static final int INFLATE

Used to create a stream that will be used for data decompression. In this mode, you may NOT use the method writeBytes.

See Also:

Constant Field Values

Constructor Detail

CompressedStream

protected CompressedStream()

CompressedStream

protected CompressedStream(Stream stream,
                           int mode)

Creates a CompressedStream object that may be used to read compressed data from the given stream, or to write compressed data to the given stream.

Parameters:

stream - input stream.

mode - its value must be either DEFLATE or INFLATE.

Since:

TotalCross 1.12

Method Detail

createDeflate

protected abstract java.lang.Object createDeflate(Stream stream)

createInflate

protected abstract java.lang.Object createInflate(Stream stream)

readBytes

public int readBytes(byte[] buf,
                     int start,
                     int count)
              throws IOException,
                     ZipException

Attempts to read count bytes to the given byte array, starting from offset start.
This method can be used only with CompressedStreams created in INFLATE mode, and should be used only for reading compressed data from the original stream, returning uncompressed data on the give byte array.

Specified by:

readBytes in class Stream

Parameters:

buf - the byte array to read data into

start - the start position in the array

count - the number of bytes to read

Throws:

IOException

ZipException

Since:

TotalCross 1.12

writeBytes

public int writeBytes(byte[] buf,
                      int start,
                      int count)
               throws IOException

Attempts to write count bytes from the given byte array, starting from offset start.
This method can be used only with CompressedStreams created in DEFLATE mode, and should be used only for compressing the contents of the given byte array, and writing the compressed data to the original stream.

Specified by:

writeBytes in class Stream

Parameters:

buf - the byte array to write data from

start - the start position in the byte array

count - the number of bytes to write

Returns:

the number of bytes actually written

Throws:

IOException

Since:

TotalCross 1.12

close

public void close()
           throws IOException

Closes this stream WITHOUT closing the underlying stream, which must be explicitly closed by the user.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

IOException - If an I/O error occurs.

Since:

TotalCross 1.12

finalize

protected void finalize()

Overrides:

finalize in class java.lang.Object