org.apache.hudi.common.util.io

Class ByteBufferBackedInputStream

java.lang.Object

java.io.InputStream

org.apache.hudi.common.util.io.ByteBufferBackedInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class ByteBufferBackedInputStream
extends InputStream

Instance of InputStream backed by ByteBuffer, implementing following functionality (on top of what's required by InputStream)

1. Seeking: enables random access by allowing to seek to an arbitrary position w/in the stream
2. (Thread-safe) Copying: enables to copy from the underlying buffer not modifying the state of the stream

NOTE: Generally methods of this class are NOT thread-safe, unless specified otherwise

Constructor Summary

Constructors

Constructor and Description
ByteBufferBackedInputStream(byte[] array)
ByteBufferBackedInputStream(byte[] array, int offset, int length)
ByteBufferBackedInputStream(ByteBuffer buf)

Method Summary

Modifier and Type	Method and Description
int	copyFrom(long pos, byte[] targetBuffer, int offset, int length) Copies at most length bytes starting from position pos into the target buffer with provided offset.
int	getPosition() Returns current position of the stream
int	read()
int	read(byte[] bytes, int offset, int length)
void	seek(long pos) Seeks to a position w/in the stream NOTE: Position is relative to the start of the stream (ie its absolute w/in this stream), with following invariant being assumed:

Methods inherited from class java.io.InputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

ByteBufferBackedInputStream

public ByteBufferBackedInputStream(ByteBuffer buf)

ByteBufferBackedInputStream

public ByteBufferBackedInputStream(byte[] array)

ByteBufferBackedInputStream

public ByteBufferBackedInputStream(byte[] array,
                                   int offset,
                                   int length)

Method Detail

read

public int read()

Specified by:

read in class InputStream

read

public int read(@Nonnull
                byte[] bytes,
                int offset,
                int length)

Overrides:

read in class InputStream

getPosition

public int getPosition()

Returns current position of the stream

seek

public void seek(long pos)

Seeks to a position w/in the stream NOTE: Position is relative to the start of the stream (ie its absolute w/in this stream), with following invariant being assumed:

0 <= pos <= length (of the stream)

This method is NOT thread-safe

Parameters:

pos - target position to seek to w/in the holding buffer

copyFrom

public int copyFrom(long pos,
                    byte[] targetBuffer,
                    int offset,
                    int length)

Copies at most length bytes starting from position pos into the target buffer with provided offset. Returns number of bytes copied from the backing buffer NOTE: This does not change the current position of the stream and is thread-safe

Parameters:

pos - absolute position w/in stream to read from

targetBuffer - target buffer to copy into

offset - target buffer offset to copy at

length - length of the sequence to copy

Returns:

number of bytes copied