de.ruedigermoeller.heapoff.structs

Class FSTStructAllocator

java.lang.Object

de.ruedigermoeller.heapoff.structs.FSTStructAllocator

Direct Known Subclasses:

FSTTypedStructAllocator

public class FSTStructAllocator
extends Object

Copyright (c) 2012, Ruediger Moeller. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

Date: 04.10.13 Time: 20:51 To change this template use File | Settings | File Templates.

Field Summary

Fields

Modifier and Type	Field and Description
protected byte[]	chunk
protected int	chunkIndex
protected int	chunkSize

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FSTStructAllocator()
	FSTStructAllocator(int chunkSizeBytes) Create a Structallocator with given chunk size in bytes.

Method Summary

Methods

Modifier and Type	Method and Description
static FSTStruct	createStructPointer(byte[] b, int index)
protected FSTStructFactory	getFactory()
static FSTStruct	getVolatileStructPointer(byte[] b, int index)
<X extends FSTStruct> StructArray<X>	newArray(int size, X templ) create a new struct array of same type as template
<K extends FSTStruct,V extends FSTStruct> StructMap<K,V>	newMap(int size, K keyTemplate, V valueTemplate) create a fixed size struct hashmap.
static <C extends FSTStruct> C	newPointer(Class<C> clazz)
<S extends FSTStruct> S	newStruct(S aTemplate) allocate a Struct instance from an arbitrary template.
static <T extends FSTStruct> T	toStruct(T onHeapTemplate)

Methods inherited from class java.lang.Object

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

Field Detail

chunkSize

protected int chunkSize

chunk

protected byte[] chunk

chunkIndex

protected int chunkIndex

Constructor Detail

FSTStructAllocator

protected FSTStructAllocator()

FSTStructAllocator

public FSTStructAllocator(int chunkSizeBytes)

Create a Structallocator with given chunk size in bytes. If allocated structs are larger than the given size, a new bytearray is created for the allocation.

Parameters:

chunkSizeBytes -

Method Detail

createStructPointer

public static FSTStruct createStructPointer(byte[] b,
                            int index)

Parameters:

b -

index -

Returns:

a new allocated pointer matching struct type stored in b[]

toStruct

public static <T extends FSTStruct> T toStruct(T onHeapTemplate)

Type Parameters:

T -

Parameters:

onHeapTemplate -

Returns:

return a byte array based struct instance for given on-heap template. Allocates a new byte[] with each call

getVolatileStructPointer

public static FSTStruct getVolatileStructPointer(byte[] b,
                                 int index)

Parameters:

b -

index -

Returns:

a pointer matching struct type stored in b[] from the thread local cache

newPointer

public static <C extends FSTStruct> C newPointer(Class<C> clazz)

Type Parameters:

C -

Parameters:

clazz -

Returns:

a newly allocated pointer matching. use baseOn to point it to a meaningful location

newArray

public <X extends FSTStruct> StructArray<X> newArray(int size,
                                            X templ)

create a new struct array of same type as template

Parameters:

size -

Returns:

newMap

public <K extends FSTStruct,V extends FSTStruct> StructMap<K,V> newMap(int size,
                                                              K keyTemplate,
                                                              V valueTemplate)

create a fixed size struct hashmap. Note it should be of fixed types for keys and values, as the space for those is allocated directly. Additionally keys and values are stored 'in-place' without references. (for allocation if templateless cosntructore has been used)

Type Parameters:

K -

Parameters:

size -

keyTemplate -

Returns:

newStruct

public <S extends FSTStruct> S newStruct(S aTemplate)

allocate a Struct instance from an arbitrary template. This is provided to avoid having to construct tons of "allocator" instances.

Type Parameters:

S -

Parameters:

aTemplate -

Returns:

getFactory

protected FSTStructFactory getFactory()