Package org.github.jamm

Class MemoryMeter

java.lang.Object

org.github.jamm.MemoryMeter

public class MemoryMeter
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MemoryMeter.Guess

Constructor Summary

Constructors

Constructor	Description
MemoryMeter()

Method Summary

Modifier and Type	Method	Description
static void	agentmain(java.lang.String options, java.lang.instrument.Instrumentation inst)
long	countChildren(java.lang.Object object)
MemoryMeter	enableDebug()	Makes this MemoryMeter prints the classes tree to System.out when measuring
MemoryMeter	enableDebug(int depth)	Makes this MemoryMeter prints the classes tree to System.out up to the specified depth when measuring
static boolean	hasInstrumentation()
MemoryMeter	ignoreKnownSingletons()	return a MemoryMeter that ignores space occupied by known singletons such as Class objects and Enums
MemoryMeter	ignoreNonStrongReferences()	return a MemoryMeter that ignores space occupied by known singletons such as Class objects and Enums
MemoryMeter	ignoreOuterClassReference()
long	measure(java.lang.Object object)
long	measureDeep(java.lang.Object object)
MemoryMeter	omitSharedBufferOverhead()
static void	premain(java.lang.String options, java.lang.instrument.Instrumentation inst)
MemoryMeter	withGuessing(MemoryMeter.Guess guess)
MemoryMeter	withTrackerProvider(java.util.concurrent.Callable<java.util.Set<java.lang.Object>> trackerProvider)

Methods inherited from class java.lang.Object

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

Constructor Detail

MemoryMeter

public MemoryMeter()

Method Detail

premain

public static void premain(java.lang.String options,
                           java.lang.instrument.Instrumentation inst)

agentmain

public static void agentmain(java.lang.String options,
                             java.lang.instrument.Instrumentation inst)

hasInstrumentation

public static boolean hasInstrumentation()

withTrackerProvider

public MemoryMeter withTrackerProvider(java.util.concurrent.Callable<java.util.Set<java.lang.Object>> trackerProvider)

Parameters:

trackerProvider -

Returns:

a MemoryMeter with the given provider

omitSharedBufferOverhead

public MemoryMeter omitSharedBufferOverhead()

Returns:

a MemoryMeter that only counts the bytes remaining in a ByteBuffer in measureDeep, rather than the full size of the backing array. TODO: handle other types of Buffers

withGuessing

public MemoryMeter withGuessing(MemoryMeter.Guess guess)

Returns:

a MemoryMeter that permits guessing the size of objects if instrumentation isn't enabled

ignoreOuterClassReference

public MemoryMeter ignoreOuterClassReference()

Returns:

a MemoryMeter that ignores the size of an outer class reference

ignoreKnownSingletons

public MemoryMeter ignoreKnownSingletons()

return a MemoryMeter that ignores space occupied by known singletons such as Class objects and Enums

ignoreNonStrongReferences

public MemoryMeter ignoreNonStrongReferences()

return a MemoryMeter that ignores space occupied by known singletons such as Class objects and Enums

enableDebug

public MemoryMeter enableDebug()

Makes this MemoryMeter prints the classes tree to System.out when measuring

enableDebug

public MemoryMeter enableDebug(int depth)

Makes this MemoryMeter prints the classes tree to System.out up to the specified depth when measuring

Parameters:

depth - the maximum depth for which the class tree must be printed

measure

public long measure(java.lang.Object object)

Returns:

the shallow memory usage of @param object

Throws:

java.lang.NullPointerException - if object is null

measureDeep

public long measureDeep(java.lang.Object object)

Returns:

the memory usage of @param object including referenced objects

Throws:

java.lang.NullPointerException - if object is null

countChildren

public long countChildren(java.lang.Object object)

Returns:

the number of child objects referenced by @param object

Throws:

java.lang.NullPointerException - if object is null