Package org.apache.commons.compress.compressors.z

Class ZCompressorInputStream

java.lang.Object

java.io.InputStream

org.apache.commons.compress.compressors.CompressorInputStream

org.apache.commons.compress.compressors.lzw.LZWInputStream

org.apache.commons.compress.compressors.z.ZCompressorInputStream

All Implemented Interfaces:

Closeable, AutoCloseable, InputStreamStatistics

public class ZCompressorInputStream
extends LZWInputStream

Input stream that decompresses .Z files.

Since:

1.7

This class is not thread-safe

Field Summary

Fields inherited from class org.apache.commons.compress.compressors.lzw.LZWInputStream

DEFAULT_CODE_SIZE, in, UNUSED_PREFIX

Constructor Summary

Constructors

Constructor	Description
ZCompressorInputStream(InputStream inputStream)	Constructs a new instance.
ZCompressorInputStream(InputStream inputStream, int memoryLimitInKiB)	Constructs a new instance.

Method Summary

Modifier and Type	Method	Description
protected int	addEntry(int previousCode, byte character)	Add a new entry to the dictionary.
protected int	decompressNextSymbol()	Reads the next code and expand it.
static boolean	matches(byte[] signature, int length)	Checks if the signature matches what is expected for a Unix compress file.
protected int	readNextCode()	Reads the next code from the stream.

Methods inherited from class org.apache.commons.compress.compressors.lzw.LZWInputStream

addEntry, addRepeatOfPreviousCode, close, expandCodeToOutputStack, getClearCode, getCodeSize, getCompressedCount, getPrefix, getPrefixesLength, getTableSize, incrementCodeSize, initializeTables, initializeTables, read, read, resetCodeSize, resetPreviousCode, setClearCode, setCodeSize, setPrefix, setTableSize

Methods inherited from class org.apache.commons.compress.compressors.CompressorInputStream

count, count, getBytesRead, getCount, getUncompressedCount, pushedBackBytes

Methods inherited from class java.io.InputStream

available, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.compress.utils.InputStreamStatistics

getUncompressedCount

Constructor Details

ZCompressorInputStream

public ZCompressorInputStream(InputStream inputStream)
                       throws IOException

Constructs a new instance.

Parameters:

inputStream - The underlying input stream.

Throws:

IOException - if an I/O error occurs.

ZCompressorInputStream

public ZCompressorInputStream(InputStream inputStream,
 int memoryLimitInKiB)
                       throws IOException

Constructs a new instance.

Parameters:

inputStream - The underlying input stream.

memoryLimitInKiB - maximum allowed estimated memory usage in kibibytes.

Throws:

IOException - if an I/O error occurs.

Method Details

matches

public static boolean matches(byte[] signature,
 int length)

Checks if the signature matches what is expected for a Unix compress file.

Parameters:

signature - the bytes to check

length - the number of bytes to check

Returns:

true, if this stream is a Unix compress compressed stream, false otherwise

Since:

1.9

addEntry

protected int addEntry(int previousCode,
 byte character)
                throws IOException

Add a new entry to the dictionary.

This method is only protected for technical reasons and is not part of Commons Compress' published API. It may change or disappear without warning.

Specified by:

addEntry in class LZWInputStream

Parameters:

previousCode - the previous code

character - the next character to append

Returns:

the new code

Throws:

IOException - on error

decompressNextSymbol

protected int decompressNextSymbol()
                            throws IOException

Reads the next code and expand it.

This method is only protected for technical reasons and is not part of Commons Compress' published API. It may change or disappear without warning.

Specified by:

decompressNextSymbol in class LZWInputStream

Returns:

the expanded next code, negative on EOF

Throws:

IOException - on error

readNextCode

protected int readNextCode()
                    throws IOException

Reads the next code from the stream.

This method is only protected for technical reasons and is not part of Commons Compress' published API. It may change or disappear without warning.

Overrides:

readNextCode in class LZWInputStream

Returns:

the next code

Throws:

IOException - on error