org.apache.beam.runners.dataflow.util

Class RandomAccessData

java.lang.Object

org.apache.beam.runners.dataflow.util.RandomAccessData

@NotThreadSafe
public class RandomAccessData
extends java.lang.Object

An elastic-sized byte array which allows you to manipulate it as a stream, or access it directly. This allows for a quick succession of moving bytes from an InputStream to this wrapper to be used as an OutputStream and vice versa. This wrapper also provides random access to bytes stored within. This wrapper allows users to finely control the number of byte copies that occur.

Anything stored within the in-memory buffer from offset size() is considered temporary unused storage.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RandomAccessData.RandomAccessDataCoder A Coder which encodes the valid parts of this stream.
static class	RandomAccessData.UnsignedLexicographicalComparator A Comparator that compares two byte arrays lexicographically.

Field Summary

Fields

Modifier and Type	Field and Description
static RandomAccessData.UnsignedLexicographicalComparator	UNSIGNED_LEXICOGRAPHICAL_COMPARATOR

Constructor Summary

Constructors

Constructor and Description
RandomAccessData() Constructs a RandomAccessData with a default buffer size.
RandomAccessData(byte[] initialBuffer) Constructs a RandomAccessData with the initial buffer.
RandomAccessData(int initialBufferSize) Constructs a RandomAccessData with the given buffer size.

Method Summary

Modifier and Type	Method and Description
byte[]	array() Returns the backing array.
java.io.InputStream	asInputStream(int offset, int length) Returns an InputStream wrapper which supplies the portion of this backing byte buffer starting at offset and up to length bytes.
java.io.OutputStream	asOutputStream() Returns an output stream which writes to the backing buffer from the current position.
RandomAccessData	copy() Returns a copy of this RandomAccessData.
boolean	equals(java.lang.Object other)
int	hashCode()
RandomAccessData	increment() Returns a RandomAccessData that is the smallest value of same length which is strictly greater than this.
void	readFrom(java.io.InputStream inStream, int offset, int length) Reads length bytes from the specified input stream writing them into the backing data store starting at offset.
void	resetTo(int position) Resets the end of the stream to the specified position.
int	size() Returns the number of bytes in the backing array that are valid.
java.lang.String	toString()
void	writeTo(java.io.OutputStream out, int offset, int length) Writes length bytes starting at offset from the backing data store to the specified output stream.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

UNSIGNED_LEXICOGRAPHICAL_COMPARATOR

public static final RandomAccessData.UnsignedLexicographicalComparator UNSIGNED_LEXICOGRAPHICAL_COMPARATOR

Constructor Detail

RandomAccessData

public RandomAccessData()

Constructs a RandomAccessData with a default buffer size.

RandomAccessData

public RandomAccessData(byte[] initialBuffer)

Constructs a RandomAccessData with the initial buffer.

RandomAccessData

public RandomAccessData(int initialBufferSize)

Constructs a RandomAccessData with the given buffer size.

Method Detail

increment

public RandomAccessData increment()
                           throws java.io.IOException

Returns a RandomAccessData that is the smallest value of same length which is strictly greater than this. Note that if this is empty or is all 0xFF then a token value of positive infinity is returned.

The RandomAccessData.UnsignedLexicographicalComparator supports comparing RandomAccessData with support for positive infinitiy.

Throws:

java.io.IOException

array

public byte[] array()

Returns the backing array.

size

public int size()

Returns the number of bytes in the backing array that are valid.

resetTo

public void resetTo(int position)

Resets the end of the stream to the specified position.

asOutputStream

public java.io.OutputStream asOutputStream()

Returns an output stream which writes to the backing buffer from the current position. Note that the internal buffer will grow as required to accomodate all data written.

asInputStream

public java.io.InputStream asInputStream(int offset,
                                         int length)

Returns an InputStream wrapper which supplies the portion of this backing byte buffer starting at offset and up to length bytes. Note that the returned InputStream is only a wrapper and any modifications to the underlying RandomAccessData will be visible by the InputStream.

writeTo

public void writeTo(java.io.OutputStream out,
                    int offset,
                    int length)
             throws java.io.IOException

Writes length bytes starting at offset from the backing data store to the specified output stream.

Throws:

java.io.IOException

readFrom

public void readFrom(java.io.InputStream inStream,
                     int offset,
                     int length)
              throws java.io.IOException

Reads length bytes from the specified input stream writing them into the backing data store starting at offset.

Note that the in memory stream will be grown to ensure there is enough capacity.

Throws:

java.io.IOException

copy

public RandomAccessData copy()
                      throws java.io.IOException

Returns a copy of this RandomAccessData.

Throws:

java.io.IOException

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object