JP.co.Hitachi.soft.jvm

Class MemoryInfo

java.lang.Object

JP.co.Hitachi.soft.jvm.MemoryInfo

public class MemoryInfo
extends java.lang.Object

You can acquire the memory information of GC directly from a Java program.

For example, the space that is being currently used is calculated with the following expression.
getXXXTotalMemory()－getXXXFreeMemory()
Note:XXX expresses one of Eden,Survivor,Tenured,Metaspace.

Method Summary

Modifier and Type	Method and Description
static long	getEdenFreeMemory() Acquires the free space in the Eden area.
static long	getEdenMaxMemory() Acquires the maximum space used by the Eden area.
static long	getEdenTotalMemory() Acquires the commited space in the Eden area.
static long	getMetaspaceFreeMemory() Acquires the free space in the Metaspace.
static long	getMetaspaceMaxMemory() Acquires the maximum space used by the Metaspace.
static long	getMetaspaceTotalMemory() Acquires the commited space in the Metaspace.
static long	getPermFreeMemory() Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceFreeMemory().
static long	getPermMaxMemory() Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceMaxMemory().
static long	getPermTotalMemory() Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceTotalMemory().
static long	getSurvivorFreeMemory() Acquires the free space in the Survivor area.
static long	getSurvivorMaxMemory() Acquires the maximum space used by the Survivor area.
static long	getSurvivorTotalMemory() Acquires the commited space in the Survivor area.
static long	getTenuredFreeMemory() Acquires the free space in the Tenured area.
static long	getTenuredMaxMemory() Acquires the maximum space used by the Tenured area.
static long	getTenuredTotalMemory() Acquires the commited space in the Tenured area.

Methods inherited from class java.lang.Object

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

Method Detail

getEdenFreeMemory

public static long getEdenFreeMemory()

Acquires the free space in the Eden area.

Returns:

This method returns the free space (number of bytes) in the Eden area as a long type.

getEdenTotalMemory

public static long getEdenTotalMemory()

Acquires the commited space in the Eden area.

Returns:

This method returns the commited space (number of bytes) in the Eden area as a long type.

getEdenMaxMemory

public static long getEdenMaxMemory()

Acquires the maximum space used by the Eden area.

Returns:

This method returns the maximum space (number of bytes) used by the Eden area as a long type.

Note:If the G1GC is used, -1 is returned.

getSurvivorFreeMemory

public static long getSurvivorFreeMemory()

Acquires the free space in the Survivor area.

Returns:

This method returns the free space (number of bytes) in the Survivor area as a long type.

getSurvivorTotalMemory

public static long getSurvivorTotalMemory()

Acquires the commited space in the Survivor area.

Returns:

This method returns the commited space (number of bytes) in the Survivor area as a long type.

getSurvivorMaxMemory

public static long getSurvivorMaxMemory()

Acquires the maximum space used by the Survivor area.

Returns:

This method returns the maximum space (number of bytes) used by the Survivor area as a long type.

Note:If the G1GC is used, -1 is returned.

getTenuredFreeMemory

public static long getTenuredFreeMemory()

Acquires the free space in the Tenured area.

Returns:

This method returns the free space (number of bytes) in the Tenured area as a long type.

getTenuredTotalMemory

public static long getTenuredTotalMemory()

Acquires the commited space in the Tenured area.

Returns:

This method returns the commited space (number of bytes) in the Tenured area as a long type.

getTenuredMaxMemory

public static long getTenuredMaxMemory()

Acquires the maximum space used by the Tenured area.

Returns:

This method returns the maximum space (number of bytes) used by the Tenured area as a long type.

Note:If the G1GC is used, the maximum space used by the Java Heap is returned.

getPermFreeMemory

public static long getPermFreeMemory()

Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceFreeMemory().

Returns:

1

Since:

10-10

See Also:

getMetaspaceFreeMemory()

getPermTotalMemory

public static long getPermTotalMemory()

Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceTotalMemory().

Returns:

1

Since:

10-10

See Also:

getMetaspaceTotalMemory()

getPermMaxMemory

public static long getPermMaxMemory()

Deprecated. For version 10-10 or later, we recommend that you use getMetaspaceMaxMemory().

Returns:

1

Since:

10-10

See Also:

getMetaspaceMaxMemory()

getMetaspaceFreeMemory

public static long getMetaspaceFreeMemory()

Acquires the free space in the Metaspace.

Returns:

This method returns the free space (number of bytes) in the Metaspace as a long type.

Since:

10-10

getMetaspaceTotalMemory

public static long getMetaspaceTotalMemory()

Acquires the commited space in the Metaspace.

Returns:

This method returns the commited space (number of bytes) in the Metaspace as a long type.

Since:

10-10

getMetaspaceMaxMemory

public static long getMetaspaceMaxMemory()

Acquires the maximum space used by the Metaspace.

Returns:

This method returns the maximum space used by the Metaspace (number of bytes) as a long type.

Note:If the MaxMetaspaceSize option is not specified, the method returns -1.

Since:

10-10