org.xerial.snappy

Class SnappyFramedInputStream

java.lang.Object

java.io.InputStream

org.xerial.snappy.SnappyFramedInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.nio.channels.Channel, java.nio.channels.ReadableByteChannel

public final class SnappyFramedInputStream
extends java.io.InputStream
implements java.nio.channels.ReadableByteChannel

Implements the x-snappy-framed as an InputStream and ReadableByteChannel.

Since:

1.1.0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	SnappyFramedInputStream.FrameAction
static class	SnappyFramedInputStream.FrameData
static class	SnappyFramedInputStream.FrameMetaData

Field Summary

Fields

Modifier and Type	Field and Description
private byte[]	buffer Buffer contains a copy of the uncompressed data for the block.
private boolean	closed Indicates if this instance has been closed.
private boolean	eof Indicates if we have reached the EOF on input.
private java.nio.ByteBuffer	frameHeader
private java.nio.ByteBuffer	input A single frame read from the underlying InputStream.
private int	position The next position to read from buffer.
private java.nio.channels.ReadableByteChannel	rbc
private java.nio.ByteBuffer	uncompressedDirect The decompressed data from input.
private int	valid The position in input buffer to read to.
private boolean	verifyChecksums

Constructor Summary

Constructors

Constructor and Description
SnappyFramedInputStream(java.io.InputStream in) Creates a Snappy input stream to read data from the specified underlying input stream.
SnappyFramedInputStream(java.io.InputStream in, boolean verifyChecksums) Creates a Snappy input stream to read data from the specified underlying input stream.
SnappyFramedInputStream(java.nio.channels.ReadableByteChannel in) Creates a Snappy input stream to read data from the specified underlying channel.
SnappyFramedInputStream(java.nio.channels.ReadableByteChannel in, boolean verifyChecksums) Creates a Snappy input stream to read data from the specified underlying channel.

Method Summary

Modifier and Type	Method and Description
private void	allocateBuffersBasedOnSize(int size)
int	available()
void	close()
private boolean	ensureBuffer()
private int	getCrc32c(java.nio.ByteBuffer content)
private SnappyFramedInputStream.FrameData	getFrameData(java.nio.ByteBuffer content)
private SnappyFramedInputStream.FrameMetaData	getFrameMetaData(java.nio.ByteBuffer frameHeader)
boolean	isOpen()
int	read()
int	read(byte[] output, int offset, int length)
int	read(java.nio.ByteBuffer dst)
private boolean	readBlockHeader()
long	transferTo(java.io.OutputStream os) Transfers the entire content of this InputStream to os.
long	transferTo(java.nio.channels.WritableByteChannel wbc) Transfers the entire content of this ReadableByteChannel to wbc.

Methods inherited from class java.io.InputStream

mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

rbc

private final java.nio.channels.ReadableByteChannel rbc

frameHeader

private final java.nio.ByteBuffer frameHeader

verifyChecksums

private final boolean verifyChecksums

input

private java.nio.ByteBuffer input

A single frame read from the underlying InputStream.

uncompressedDirect

private java.nio.ByteBuffer uncompressedDirect

The decompressed data from input.

closed

private boolean closed

Indicates if this instance has been closed.

eof

private boolean eof

Indicates if we have reached the EOF on input.

valid

private int valid

The position in input buffer to read to.

position

private int position

The next position to read from buffer.

buffer

private byte[] buffer

Buffer contains a copy of the uncompressed data for the block.

Constructor Detail

SnappyFramedInputStream

public SnappyFramedInputStream(java.io.InputStream in)
                        throws java.io.IOException

Creates a Snappy input stream to read data from the specified underlying input stream.

Parameters:

in - the underlying input stream. Must not be null.

Throws:

java.io.IOException

SnappyFramedInputStream

public SnappyFramedInputStream(java.io.InputStream in,
                               boolean verifyChecksums)
                        throws java.io.IOException

Creates a Snappy input stream to read data from the specified underlying input stream.

Parameters:

in - the underlying input stream. Must not be null.

verifyChecksums - if true, checksums in input stream will be verified

Throws:

java.io.IOException

SnappyFramedInputStream

public SnappyFramedInputStream(java.nio.channels.ReadableByteChannel in)
                        throws java.io.IOException

Creates a Snappy input stream to read data from the specified underlying channel.

Parameters:

in - the underlying readable channel. Must not be null.

Throws:

java.io.IOException

SnappyFramedInputStream

public SnappyFramedInputStream(java.nio.channels.ReadableByteChannel in,
                               boolean verifyChecksums)
                        throws java.io.IOException

Creates a Snappy input stream to read data from the specified underlying channel.

Parameters:

in - the underlying readable channel. Must not be null.

verifyChecksums - if true, checksums in input stream will be verified

Throws:

java.io.IOException

Method Detail

allocateBuffersBasedOnSize

private void allocateBuffersBasedOnSize(int size)

Parameters:

size -

read

public int read()
         throws java.io.IOException

Specified by:

read in class java.io.InputStream

Throws:

java.io.IOException

read

public int read(byte[] output,
                int offset,
                int length)
         throws java.io.IOException

Overrides:

read in class java.io.InputStream

Throws:

java.io.IOException

available

public int available()
              throws java.io.IOException

Overrides:

available in class java.io.InputStream

Throws:

java.io.IOException

isOpen

public boolean isOpen()

Specified by:

isOpen in interface java.nio.channels.Channel

read

public int read(java.nio.ByteBuffer dst)
         throws java.io.IOException

Specified by:

read in interface java.nio.channels.ReadableByteChannel

Throws:

java.io.IOException

transferTo

public long transferTo(java.io.OutputStream os)
                throws java.io.IOException

Transfers the entire content of this InputStream to os. This potentially limits the amount of buffering required to decompress content.

Unlike read(byte[], int, int), this method does not need to be called multiple times. A single call will transfer all available content. Any calls after the source has been exhausted will result in a return value of 0.

Parameters:

os - The destination to write decompressed content to.

Returns:

The number of bytes transferred.

Throws:

java.io.IOException

Since:

1.1.1

transferTo

public long transferTo(java.nio.channels.WritableByteChannel wbc)
                throws java.io.IOException

Transfers the entire content of this ReadableByteChannel to wbc. This potentially limits the amount of buffering required to decompress content.

Unlike read(ByteBuffer), this method does not need to be called multiple times. A single call will transfer all available content. Any calls after the source has been exhausted will result in a return value of 0.

Parameters:

wbc - The destination to write decompressed content to.

Returns:

The number of bytes transferred.

Throws:

java.io.IOException

Since:

1.1.1

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.nio.channels.Channel

Overrides:

close in class java.io.InputStream

Throws:

java.io.IOException

ensureBuffer

private boolean ensureBuffer()
                      throws java.io.IOException

Throws:

java.io.IOException

readBlockHeader

private boolean readBlockHeader()
                         throws java.io.IOException

Throws:

java.io.IOException

getFrameMetaData

private SnappyFramedInputStream.FrameMetaData getFrameMetaData(java.nio.ByteBuffer frameHeader)
                                                        throws java.io.IOException

Parameters:

frameHeader -

Returns:

Throws:

java.io.IOException

getFrameData

private SnappyFramedInputStream.FrameData getFrameData(java.nio.ByteBuffer content)
                                                throws java.io.IOException

Parameters:

content -

Returns:

Throws:

java.io.IOException

getCrc32c

private int getCrc32c(java.nio.ByteBuffer content)