Package org.aksw.commons.io.hadoop

Class SeekableInputStreams

java.lang.Object

org.aksw.commons.io.hadoop.SeekableInputStreams

public class SeekableInputStreams
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	SeekableInputStreams.GetPositionFn<T>
static interface	SeekableInputStreams.SetPositionFn<T>

Constructor Summary

Constructors

Constructor	Description
SeekableInputStreams()

Method Summary

Modifier and Type	Method	Description
static ReadableChannelWithBlockAdvertisement	advertiseEndOfBlock(InputStream decodedIn)	The argument for invoking this methods must be a seekable input streams that implements hadoop's protocol for splittable codecs using READ_MODE.BYBLOCK.
static ReadableChannelWithBlockAdvertisement	advertiseEndOfBlock(InputStream decodedIn, int endOfBlockMarker)
static <T extends ReadableByteChannel> SeekableInputStream	create(InputStream in, GetPosition getPosition, SetPosition setPosition)
static SeekableInputStream	create(InputStream in, org.apache.hadoop.fs.Seekable seekable)
static <T extends ReadableByteChannel> SeekableInputStream	create(SeekableByteChannel channel)
static <T extends ReadableByteChannel> SeekableInputStream	create(SeekableReadableChannel<byte[]> channel)
static <T extends ReadableByteChannel> SeekableInputStream	create(T channel, SeekableInputStreams.GetPositionFn<? super T> getPosition, SeekableInputStreams.SetPositionFn<? super T> setPosition)
static org.apache.hadoop.fs.Seekable	createSeekable(GetPosition getPosition, SetPosition setPosition)
static SeekableReadableChannel<byte[]>	wrap(SeekableInputStream in)	Bridge SeekableInputStream to the channel API

Methods inherited from class java.lang.Object

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

Constructor Details

SeekableInputStreams

public SeekableInputStreams()

Method Details

createSeekable

public static org.apache.hadoop.fs.Seekable createSeekable(GetPosition getPosition,
 SetPosition setPosition)

create

public static <T extends ReadableByteChannel>
SeekableInputStream create(T channel,
 SeekableInputStreams.GetPositionFn<? super T> getPosition,
 SeekableInputStreams.SetPositionFn<? super T> setPosition)

wrap

public static SeekableReadableChannel<byte[]> wrap(SeekableInputStream in)

Bridge SeekableInputStream to the channel API

create

public static <T extends ReadableByteChannel>
SeekableInputStream create(SeekableByteChannel channel)

create

public static <T extends ReadableByteChannel>
SeekableInputStream create(SeekableReadableChannel<byte[]> channel)

create

public static <T extends ReadableByteChannel>
SeekableInputStream create(InputStream in,
 GetPosition getPosition,
 SetPosition setPosition)

create

public static SeekableInputStream create(InputStream in,
 org.apache.hadoop.fs.Seekable seekable)

advertiseEndOfBlock

public static ReadableChannelWithBlockAdvertisement advertiseEndOfBlock(InputStream decodedIn)
                                                                 throws IOException

The argument for invoking this methods must be a seekable input streams that implements hadoop's protocol for splittable codecs using READ_MODE.BYBLOCK. Whereas hadoop's protocol will always read 1 byte beyond the split boundary, this wrapper will stop exactly at that boundary. Internally a push-back input stream is used to push that single "read-ahead" byte back once it is encountered. A block boundary is advertised by a call to read() by returing -2. This return value indicates that read() may be called again and will return at least one more byte. A return value of -1 indicates "end of file" just as usual.

Parameters:

decodedIn -

endOfBlockMarker - The value to return when an end of block is detected

Returns:

Throws:

IOException

advertiseEndOfBlock

public static ReadableChannelWithBlockAdvertisement advertiseEndOfBlock(InputStream decodedIn,
 int endOfBlockMarker)
                                                                 throws IOException

Throws:

IOException