Class TokenMapFileSharedBuffers

java.lang.Object

io.nosqlbench.datamappers.functions.rainbow.TokenMapFileSharedBuffers

public class TokenMapFileSharedBuffers
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
static final TokenMapFileSharedBuffers	INSTANCE

Method Summary

Modifier and Type	Method	Description
static ByteBuffer	getByteBuffer(String filename, boolean instanced, boolean ascending)	Find and load the ByteBuffer which can be read at the specified location.

Methods inherited from class java.lang.Object

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

Field Details

INSTANCE

public static final TokenMapFileSharedBuffers INSTANCE

Method Details

getByteBuffer

public static ByteBuffer getByteBuffer(String filename,
 boolean instanced,
 boolean ascending)

Find and load the ByteBuffer which can be read at the specified location. This will only be loaded into memory once. All callers will get access to the same logical source data. Whether or not the caller gets its own buffer tracking state (see Buffer). If each caller will use the Buffer API for incremental reads, where callers could possibly read the same records, then separate instanced buffers are advised.

However, if you are planning to use position-oriented access to the buffer only, then it is not necessary to ask for instanced buffers. In some usage patterns, it may be desirable to provide a single logical view of buffer reader position across multiple threads. In this case, setting instanced to false is necessary.

Parameters:

filename - The location of the source data for the buffer.

instanced - If true, each caller gets a wrapped buffer object with its own tracking state

ascending -

Returns:

An instance of a ByteBuffer