Package org.apache.lucene.util.fst

Class OffHeapFSTStore

java.lang.Object

org.apache.lucene.util.fst.OffHeapFSTStore

All Implemented Interfaces:

Accountable, FSTReader, FSTStore

public final class OffHeapFSTStore
extends Object
implements FSTStore

Provides off heap storage of finite state machine (FST), using underlying index input instead of byte store on heap

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields inherited from interface org.apache.lucene.util.Accountable

NULL_ACCOUNTABLE

Constructor Summary

Constructors

Constructor	Description
OffHeapFSTStore()

Method Summary

Modifier and Type	Method	Description
FST.BytesReader	getReverseBytesReader()	Get the reverse BytesReader for this FST
FSTStore	init(DataInput in, long numBytes)	Initialize the FSTStore
long	ramBytesUsed()	Return the memory usage of this object in bytes.
long	size()
void	writeTo(DataOutput out)	Write this FST to another DataOutput

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.lucene.util.Accountable

getChildResources

Constructor Detail

OffHeapFSTStore

public OffHeapFSTStore()

Method Detail

init

public FSTStore init(DataInput in,
                     long numBytes)
              throws IOException

Description copied from interface: FSTStore

Initialize the FSTStore

Specified by:

init in interface FSTStore

Parameters:

in - the DataInput to read from

numBytes - the number of bytes to read

Returns:

this FSTStore

Throws:

IOException - if exception occurred during reading the DataInput

ramBytesUsed

public long ramBytesUsed()

Description copied from interface: Accountable

Return the memory usage of this object in bytes. Negative values are illegal.

Specified by:

ramBytesUsed in interface Accountable

size

public long size()

getReverseBytesReader

public FST.BytesReader getReverseBytesReader()

Description copied from interface: FSTReader

Get the reverse BytesReader for this FST

Specified by:

getReverseBytesReader in interface FSTReader

Returns:

the reverse BytesReader

writeTo

public void writeTo(DataOutput out)
             throws IOException

Description copied from interface: FSTReader

Write this FST to another DataOutput

Specified by:

writeTo in interface FSTReader

Parameters:

out - the DataOutput

Throws:

IOException - if exception occurred during writing