ifs.fnd.agent

Class InstrumentationAgent

java.lang.Object

ifs.fnd.agent.InstrumentationAgent

public class InstrumentationAgent
extends java.lang.Object

Class containing static methods which can be used to provide an approximation of the memory used by some object. Since this is implemented as a Java agent, it needs to be initialized like this (command line): -javaagent:ifs-fnd-instrumentation.jar That same jar-file also has to be on the classpath.

Constructor Summary

Constructors

Constructor and Description
InstrumentationAgent()

Method Summary

Modifier and Type	Method and Description
static long	deepSize(java.lang.Object object) Return an approximation of the memory consumed by the entire object graph rooted at the object to estimate.
static boolean	isInitialized() Used to check if the agent has been initialized or not.
static void	premain(java.lang.String agentArgs, java.lang.instrument.Instrumentation instr)
static long	shallowSize(java.lang.Object object) Returns an approximation of the amount of memory consumed by the specified object.

Methods inherited from class java.lang.Object

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

Constructor Detail

InstrumentationAgent

public InstrumentationAgent()

Method Detail

premain

public static void premain(java.lang.String agentArgs,
                           java.lang.instrument.Instrumentation instr)

isInitialized

public static final boolean isInitialized()

Used to check if the agent has been initialized or not. It can be used only if it has been initialized.

Returns:

true if the agent has been initialized

shallowSize

public static final long shallowSize(java.lang.Object object)

Returns an approximation of the amount of memory consumed by the specified object.

Parameters:

object - the object to size

Returns:

an approximation of the memory consumed by the specified object, in bytes

deepSize

public static final long deepSize(java.lang.Object object)

Return an approximation of the memory consumed by the entire object graph rooted at the object to estimate.

Parameters:

object - The root object

Returns:

An approximation of the memory used, in bytes