Package io.pravega.common.util

Interface BufferView.Reader

All Known Implementing Classes:

AbstractBufferView.AbstractReader

Enclosing interface:

BufferView

public static interface BufferView.Reader

Defines a reader for a BufferView.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	BufferView.Reader.OutOfBoundsException	Exception that is thrown whenever an attempt is made to read beyond the bounds of a BufferView.

Method Summary

Modifier and Type	Method	Description
int	available()	Gets a value indicating the number of bytes available to read.
byte	readByte()	Reads one byte and advances the reader position by 1.
int	readBytes(java.nio.ByteBuffer byteBuffer)	Reads a number of bytes into the given ByteBuffer using the most efficient method for the implementation of this BufferView.
ArrayView	readFully(int bufferSize)	Copies all the remaining bytes from this BufferView.Reader into a new ArrayView.
int	readInt()	Reads 4 bytes (and advances the reader position by 4) and composes a 32-bit Integer (Big-Endian).
long	readLong()	Reads 8 bytes (and advances the reader position by 4) and composes a 64-bit Long (Big-Endian).
BufferView	readSlice(int length)	Returns a BufferView that is a representation of the next bytes starting at the given position.

Method Detail

available

int available()

Gets a value indicating the number of bytes available to read.

Returns:

The number of bytes available to read.

readBytes

int readBytes(java.nio.ByteBuffer byteBuffer)

Reads a number of bytes into the given ByteBuffer using the most efficient method for the implementation of this BufferView.

Parameters:

byteBuffer - The target ByteBuffer.

Returns:

The number of bytes copied. This should be

Math.min(available(), byteBuffer.remaining())

. If this returns 0, then either the given ByteBuffer has Buffer.remaining() equal to 0, or there are no more bytes to be read (available() is 0).

readByte

byte readByte()

Reads one byte and advances the reader position by 1.

Returns:

The read byte.

Throws:

BufferView.Reader.OutOfBoundsException - If available() is 0.

readInt

int readInt()

Reads 4 bytes (and advances the reader position by 4) and composes a 32-bit Integer (Big-Endian).

Returns:

The read int.

Throws:

BufferView.Reader.OutOfBoundsException - If available() is less than Integer.BYTES.

readLong

long readLong()

Reads 8 bytes (and advances the reader position by 4) and composes a 64-bit Long (Big-Endian).

Returns:

The read long.

Throws:

BufferView.Reader.OutOfBoundsException - If available() is less than Long.BYTES.

readSlice

BufferView readSlice(int length)

Returns a BufferView that is a representation of the next bytes starting at the given position. The reader position will be advanced by the requested number of bytes.

Parameters:

length - The number of bytes to slice out.

Returns:

A BufferView that represents the given bytes. This BufferView represents a view into the underlying BufferView and is not a copy of the given range.

Throws:

BufferView.Reader.OutOfBoundsException - If available() is less than length.

readFully

ArrayView readFully(int bufferSize)

Copies all the remaining bytes from this BufferView.Reader into a new ArrayView. The reader position will be set to the end of the BufferView.

Parameters:

bufferSize - The maximum number of bytes to copy at each iteration. Set to Integer.MAX_VALUE to attempt to copy the whole buffer at once.

Returns:

A new ByteArraySegment with the remaining contents of BufferView.Reader.