com.iparelan.util
Class MemoryMonitor

java.lang.Object
  java.lang.Thread
      com.iparelan.util.MemoryMonitor

All Implemented Interfaces:

Runnable

@ThreadSafe
@Immutable
@Copyright(value="Copyright © 2008, Iparelan Solutions, LLC. All rights reserved.")
public final class MemoryMonitor
extends Thread

A thread that monitors the JVM heap.

Version:

July 2008

Author:

Greg Mattes

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

static long	BYTES_PER_MEGABYTE
static long	DEFAULT_FREQUENCY
private long	frequency
private static RangeValidationStrategy<Long>	FREQUENCY_VALIDATOR
private static Logger	LOGGER
static String	MEMORY_MONITOR_LOGGER_NAME
static long	MILLISECONDS_PER_SECOND
static long	MINIMUM_FREQUENCY
private static String	NAME
static long	ONE_SECOND
static long	THIRTY_SECONDS

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

private	MemoryMonitor() Creates a MemoryMonitor.
private	MemoryMonitor(long frequency) Creates a MemoryMonitor.

Method Summary

long	getFrequency() Produces the interval between subsequent memory statistics polling operations, in milliseconds.
static MemoryMonitor	newInstance() Produces a new MemoryMonitor.
static MemoryMonitor	newInstance(long frequency) Produces a new MemoryMonitor with the specified polling frequency.
void	run()

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

NAME

private static final String NAME

MEMORY_MONITOR_LOGGER_NAME

public static final String MEMORY_MONITOR_LOGGER_NAME

See Also:

Constant Field Values

LOGGER

private static final Logger LOGGER

THIRTY_SECONDS

public static final long THIRTY_SECONDS

See Also:

Constant Field Values

ONE_SECOND

public static final long ONE_SECOND

See Also:

Constant Field Values

DEFAULT_FREQUENCY

public static final long DEFAULT_FREQUENCY

See Also:

Constant Field Values

MINIMUM_FREQUENCY

public static final long MINIMUM_FREQUENCY

See Also:

Constant Field Values

BYTES_PER_MEGABYTE

public static final long BYTES_PER_MEGABYTE

See Also:

Constant Field Values

MILLISECONDS_PER_SECOND

public static final long MILLISECONDS_PER_SECOND

See Also:

Constant Field Values

FREQUENCY_VALIDATOR

private static final RangeValidationStrategy<Long> FREQUENCY_VALIDATOR

frequency

private final long frequency

See Also:

getFrequency()

Constructor Detail

MemoryMonitor

private MemoryMonitor()

Creates a MemoryMonitor.

MemoryMonitor

private MemoryMonitor(long frequency)

Creates a MemoryMonitor.

Parameters:

frequency - Memory statistics polling interval.

Throws:

ValidationException - Iff frequency is invalid. See getFrequency() for the meaning "invalid frequency."

See Also:

getFrequency()

Method Detail

newInstance

public static MemoryMonitor newInstance()

Produces a new MemoryMonitor.

Returns:

A new MemoryMonitor.

newInstance

public static MemoryMonitor newInstance(long frequency)

Produces a new MemoryMonitor with the specified polling frequency.

Returns:

A new MemoryMonitor with the specified polling frequency.

getFrequency

public long getFrequency()

Produces the interval between subsequent memory statistics polling operations, in milliseconds. Must be greater than MINIMUM_FREQUENCY: 1000L milliseconds. A default value of 30000L milliseconds is used if no frequency is explicitly specified.

Returns:

The interval between subsequent memory statistics polling operations, in milliseconds.

run

public void run()

Specified by:

run in interface Runnable

Overrides:

run in class Thread