blasd.apex.core.memory

Class ApexMemoryHelper

java.lang.Object

blasd.apex.core.memory.ApexMemoryHelper

All Implemented Interfaces:

IApexMemoryConstants

public class ApexMemoryHelper
extends Object
implements IApexMemoryConstants

This class helps reference-sharing

Author:

Benoit Lacelle

Field Summary

Fields

Modifier and Type	Field and Description
static int	JVM_BYTES_PER_CHAR
static int	JVM_MEMORY_CHUNK
static int	JVM_STRING_HEADER
static int	NB_STRING_BEFORE_CLEAR

Fields inherited from interface blasd.apex.core.memory.IApexMemoryConstants

CHAR, DOUBLE, FLOAT, GB, INT, KB, KB_INT, LONG, MB, MB_INT, OBJECT, TB

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ApexMemoryHelper()

Method Summary

Modifier and Type	Method and Description
protected static List<Field>	computeDictionarizableFields(Class<?> clazz)
static void	dictionarize(Object data) This method will replace fields of given object with reference used by other objects.
static <T> void	dictionarizeArray(T[] array)
protected static void	dictionarizeFieldValue(Field field, Object object)
static void	dictionarizeIterable(Iterable<?> iterable)
static long	getDoubleMemory()
static long	getObjectArrayMemory(Object asArray)
static long	getObjectArrayMemory(Object[] asArray)
static long	getStringMemory(CharSequence existingRef)
static long	positivePack(int i1, int i2) It might be useful to have an long<->(int,int) packing guaranteeing both integers to be positive if the long is positive
static int	positiveUnpack1(long packed)
static int	positiveUnpack2(long packed)
static void	recursiveSize(Instrumentation instrumentation, IntPredicate identities, LongAdder totalSize, Object object)
static long	recursiveSize(Object object)
static long	recursiveSize(Object object, IntPredicate identityPredicate)
static long	recursiveSizeWithBloomFilter(Object object, long expectedObjectCardinality)
protected static void	stopDictionarizing(Class<?> clazz, Field field)

Methods inherited from class java.lang.Object

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

Field Detail

NB_STRING_BEFORE_CLEAR

public static final int NB_STRING_BEFORE_CLEAR

See Also:

Constant Field Values

JVM_MEMORY_CHUNK

public static final int JVM_MEMORY_CHUNK

See Also:

Constant Field Values

JVM_BYTES_PER_CHAR

public static final int JVM_BYTES_PER_CHAR

See Also:

Constant Field Values

JVM_STRING_HEADER

public static final int JVM_STRING_HEADER

See Also:

Constant Field Values

Constructor Detail

ApexMemoryHelper

protected ApexMemoryHelper()

Method Detail

dictionarize

public static void dictionarize(Object data)

This method will replace fields of given object with reference used by other objects. It is typically usefull to POJO which, except the spaceKey, have low cardinality

Parameters:

data -

dictionarizeFieldValue

protected static void dictionarizeFieldValue(Field field,
                                             Object object)

Parameters:

field -

object -

getStringMemory

public static long getStringMemory(CharSequence existingRef)

stopDictionarizing

protected static void stopDictionarizing(Class<?> clazz,
                                         Field field)

computeDictionarizableFields

protected static List<Field> computeDictionarizableFields(Class<?> clazz)

dictionarizeArray

public static <T> void dictionarizeArray(T[] array)

dictionarizeIterable

public static void dictionarizeIterable(Iterable<?> iterable)

recursiveSize

public static long recursiveSize(Object object)

Parameters:

object - the object to analyse

Returns:

the number of bytes consumed by given objects, taking in account the references objects

recursiveSize

public static long recursiveSize(Object object,
                                 IntPredicate identityPredicate)

recursiveSizeWithBloomFilter

public static long recursiveSizeWithBloomFilter(Object object,
                                                long expectedObjectCardinality)

recursiveSize

public static void recursiveSize(Instrumentation instrumentation,
                                 IntPredicate identities,
                                 LongAdder totalSize,
                                 Object object)

Parameters:

instrumentation - an Instrumentation able to provide the memory weight of given object

identities - an identityHashSet where to collect already handlded objects

totalSize - the LongAdder where to accumulate the memory

object - the object to analyse

getDoubleMemory

public static long getDoubleMemory()

getObjectArrayMemory

public static long getObjectArrayMemory(Object[] asArray)

getObjectArrayMemory

public static long getObjectArrayMemory(Object asArray)

positivePack

public static final long positivePack(int i1,
                                      int i2)

It might be useful to have an long<->(int,int) packing guaranteeing both integers to be positive if the long is positive

positiveUnpack1

public static final int positiveUnpack1(long packed)

positiveUnpack2

public static final int positiveUnpack2(long packed)