Package org.apache.hadoop.fs.impl

Class CombinedFileRange

java.lang.Object

org.apache.hadoop.fs.impl.FileRangeImpl

org.apache.hadoop.fs.impl.CombinedFileRange

All Implemented Interfaces:

FileRange

@Private
public class CombinedFileRange
extends FileRangeImpl

A file range that represents a set of underlying file ranges. This is used when we combine the user's FileRange objects together into a single read for efficiency.

This class is not part of the public API; it MAY BE used as a parameter to vector IO operations in FileSystem implementation code (and is)

Constructor Summary

Constructors

Constructor	Description
CombinedFileRange(long offset, long end, FileRange original)

Method Summary

Modifier and Type	Method	Description
long	getDataSize()	Get the total amount of data which is actually useful; the difference between this and FileRangeImpl.getLength() records how much data which will be discarded.
List<FileRange>	getUnderlying()	Get the list of ranges that were merged together to form this one.
boolean	merge(long otherOffset, long otherEnd, FileRange other, int minSeek, int maxSize)	Merge this input range into the current one, if it is compatible.
String	toString()

Methods inherited from class org.apache.hadoop.fs.impl.FileRangeImpl

getData, getLength, getOffset, getReference, setData, setLength, setOffset

Methods inherited from class java.lang.Object

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

Constructor Details

CombinedFileRange

public CombinedFileRange(long offset,
 long end,
 FileRange original)

Method Details

getUnderlying

public List<FileRange> getUnderlying()

Get the list of ranges that were merged together to form this one.

Returns:

the list of input ranges

merge

public boolean merge(long otherOffset,
 long otherEnd,
 FileRange other,
 int minSeek,
 int maxSize)

Merge this input range into the current one, if it is compatible. It is assumed that otherOffset is greater or equal the current offset, which typically happens by sorting the input ranges on offset.

Parameters:

otherOffset - the offset to consider merging

otherEnd - the end to consider merging

other - the underlying FileRange to add if we merge

minSeek - the minimum distance that we'll seek without merging the ranges together

maxSize - the maximum size that we'll merge into a single range

Returns:

true if we have merged the range into this one

toString

public String toString()

Overrides:

toString in class FileRangeImpl

getDataSize

public long getDataSize()

Get the total amount of data which is actually useful; the difference between this and FileRangeImpl.getLength() records how much data which will be discarded.

Returns:

a number greater than 0 and less than or equal to FileRangeImpl.getLength().