Class InflaterInputStream

All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
GZIPInputStream, ZipInputStream
public class InflaterInputStream
extends FilterInputStream

This class implements a stream filter for uncompressing data in the "deflate" compression format. It is also used as the basis for other decompression filters, such as GZIPInputStream.

Since:
1.1
See Also:
Inflater

Field Summary

Fields
Modifier and Type Field Description
protected byte[] buf

Input buffer for decompression.

protected Inflater inf

Decompressor for this stream.

protected int len

Length of input buffer.

Fields declared in class java.io.FilterInputStream

in

Constructor Summary

Constructors
Constructor Description
InflaterInputStream​(InputStream in)

Creates a new input stream with a default decompressor and buffer size.

InflaterInputStream​(InputStream in, Inflater inf)

Creates a new input stream with the specified decompressor and a default buffer size.

InflaterInputStream​(InputStream in, Inflater inf, int size)

Creates a new input stream with the specified decompressor and buffer size.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method Description
int available()

Returns 0 after EOF has been reached, otherwise always return 1.

void close()

Closes this input stream and releases any system resources associated with the stream.

protected void fill()

Fills input buffer with more data to decompress.

void mark​(int readlimit)

Marks the current position in this input stream.

boolean markSupported()

Tests if this input stream supports the mark and reset methods.

int read()

Reads a byte of uncompressed data.

int read​(byte[] b, int off, int len)

Reads uncompressed data into an array of bytes.

void reset()

Repositions this stream to the position at the time the mark method was last called on this input stream.

long skip​(long n)

Skips specified number of bytes of uncompressed data.

Methods declared in class java.io.FilterInputStream

read

Methods declared in class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods declared in class java.lang.Object

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

Field Detail

inf

protected Inflater inf

Decompressor for this stream.

buf

protected byte[] buf

Input buffer for decompression.

len

protected int len

Length of input buffer.

Constructor Detail

InflaterInputStream

public InflaterInputStream​(InputStream in,
                           Inflater inf,
                           int size)

Creates a new input stream with the specified decompressor and buffer size.

Parameters:
in - the input stream
inf - the decompressor ("inflater")
size - the input buffer size
Throws:
IllegalArgumentException - if size <= 0

InflaterInputStream

public InflaterInputStream​(InputStream in,
                           Inflater inf)

Creates a new input stream with the specified decompressor and a default buffer size.

Parameters:
in - the input stream
inf - the decompressor ("inflater")

InflaterInputStream

public InflaterInputStream​(InputStream in)

Creates a new input stream with a default decompressor and buffer size.

Parameters:
in - the input stream

Method Detail

read

public int read()
         throws IOException

Reads a byte of uncompressed data. This method will block until enough input is available for decompression.

Overrides:
read in class FilterInputStream
Returns:
the byte read, or -1 if end of compressed input is reached
Throws:
IOException - if an I/O error has occurred
See Also:
FilterInputStream.in

read

public int read​(byte[] b,
                int off,
                int len)
         throws IOException

Reads uncompressed data into an array of bytes. If len is not zero, the method will block until some input can be decompressed; otherwise, no bytes are read and 0 is returned.

Overrides:
read in class FilterInputStream
Parameters:
b - the buffer into which the data is read
off - the start offset in the destination array b
len - the maximum number of bytes read
Returns:
the actual number of bytes read, or -1 if the end of the compressed input is reached or a preset dictionary is needed
Throws:
NullPointerException - If b is null.
IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
See Also:
FilterInputStream.in

available

public int available()
              throws IOException

Returns 0 after EOF has been reached, otherwise always return 1.

Programs should not count on this method to return the actual number of bytes that could be read without blocking.

Overrides:
available in class FilterInputStream
Returns:
1 before EOF and 0 after EOF.
Throws:
IOException - if an I/O error occurs.

skip

public long skip​(long n)
          throws IOException

Skips specified number of bytes of uncompressed data.

Overrides:
skip in class FilterInputStream
Parameters:
n - the number of bytes to skip
Returns:
the actual number of bytes skipped.
Throws:
IOException - if an I/O error has occurred
IllegalArgumentException - if n < 0

close

public void close()
           throws IOException

Closes this input stream and releases any system resources associated with the stream.

Specified by:
close in interface AutoCloseable
Specified by:
close in interface Closeable
Overrides:
close in class FilterInputStream
Throws:
IOException - if an I/O error has occurred
See Also:
FilterInputStream.in

fill

protected void fill()
             throws IOException

Fills input buffer with more data to decompress.

Throws:
IOException - if an I/O error has occurred

markSupported

public boolean markSupported()

Tests if this input stream supports the mark and reset methods. The markSupported method of InflaterInputStream returns false.

Overrides:
markSupported in class FilterInputStream
Returns:
a boolean indicating if this stream type supports the mark and reset methods.
See Also:
InputStream.mark(int), InputStream.reset()

mark

public void mark​(int readlimit)

Marks the current position in this input stream.

The mark method of InflaterInputStream does nothing.

Overrides:
mark in class FilterInputStream
Parameters:
readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
See Also:
InputStream.reset()

reset

public void reset()
           throws IOException

Repositions this stream to the position at the time the mark method was last called on this input stream.

The method reset for class InflaterInputStream does nothing except throw an IOException.

Overrides:
reset in class FilterInputStream
Throws:
IOException - if this method is invoked.
See Also:
InputStream.mark(int), IOException