edu.mssm.crover.memtest
Class LeakTester

java.lang.Object
  |
  +--edu.mssm.crover.memtest.LeakTester

public abstract class LeakTester

extends java.lang.Object

Test a class use scenario for memory leaks. Memory leaks appear when unused instances are not properly unreferenced. Being still referenced, these instances cannot be garbage collected. It is generally difficult to find memory leaks and they are easy to introduce. The following methode is used by LeakTester to detect important memory leaks.

A full garbage collection (Runtime.gc() is called until no memory can be freed) is done.

The free memory is recorded.

Constructor Summary

LeakTester()

Method Summary

static long	freemem()
static void	fullGC()
abstract void	init() Initialize the experiment.
void	interact(java.lang.String message)
void	main(java.lang.String[] args) Run the test.
void	printDetails()
void	setInitialUse(int initial_use) Sets the number of times use() will be called before actually testing for memory leaks.
void	setInteractive(boolean flag) Sets the interactive mode on/off.
void	setRepeatExperiment(int times) Sets the number of times use() is called before the conclusion that no memory leak occurs can be assumed.
abstract void	use() Override to provide the use scenario.

Methods inherited from class java.lang.Object

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

Constructor Detail

LeakTester

public LeakTester()

Method Detail

main

public void main(java.lang.String[] args)

Run the test.

interact

public void interact(java.lang.String message)

printDetails

public void printDetails()

freemem

public static long freemem()

init

public abstract void init()

Initialize the experiment. Set the intial number of use() and the number of experiments here.

use

public abstract void use()

Override to provide the use scenario. A scenario should do the following:

Allocate instances from the class(es) to test,

Use this objects,

Try to release the references from this objects.

setInitialUse

public void setInitialUse(int initial_use)

Sets the number of times use() will be called before actually testing for memory leaks.

setInteractive

public void setInteractive(boolean flag)

Sets the interactive mode on/off. When the interactive mode is enabled, the LeakTester print messages on the console that indicate the steps that have been executed so far. It then waits for an input from the user on the console. The user must press return before the test proceeds. This gives the opportunity to select the exact condition when to create heap snapshots. See hat from Javasoft.

setRepeatExperiment

public void setRepeatExperiment(int times)

Sets the number of times use() is called before the conclusion that no memory leak occurs can be assumed.

fullGC

public static void fullGC()