Java in a Nutshell, 5th Edition

Name

MemoryUsage

Synopsis

A MemoryUsage object represents a snapshot of memory usage for a specified type or pool of memory. Memory usage is measured as four long values, each of which represents a number of bytes. getInit( ) returns the initial amount of memory that the Java VM requests from the operating system. getUsed( ) returns the actual number of bytes used. getCommitted( ) returns the number of bytes that the operating system has committed to the Java VM for this pool. These bytes may not all be in use, but they are not available to other processes running on the system. getMax( ) returns the maximum amount of memory that the Java VM requests for this pool. getMax( ) returns -1 if there is no defined maximum value.

public class MemoryUsage {
// Public Constructors
     public MemoryUsage(long init, long used, long committed, long max);  
// Public Class Methods
     public static MemoryUsage from(javax.management.openmbean.CompositeData cd);  
// Public Instance Methods
     public long getCommitted( );  
     public long getInit( );  
     public long getMax( );  
     public long getUsed( );  
// Public Methods Overriding Object
     public String toString( );  
}

Passed To

MemoryNotificationInfo.MemoryNotificationInfo( )

Returned By

MemoryMXBean.{getHeapMemoryUsage( ), getNonHeapMemoryUsage( )}, MemoryNotificationInfo.getUsage( ), MemoryPoolMXBean.{getCollectionUsage( ), getPeakUsage( ), getUsage( )}