Package com.bea.jvm

Provides the interfaces and the factory class for the JRockit management API.

See:
Description

Interface Summary

CallTraceElement	1.3 compatible version of StackTraceElement.
ClassLibrary	Interface to query and monitor the JVM's set of currently loaded classes and their classloaders.
ClassPreProcessor	The interface implemented by a class preprocessor.
CodeGenerationStrategy	A representation of the code generation strategy used to generate code for a method or constructor.
CompilationSystem	Interface to the compilation (machine code generation) unit of the JVM.
CPU	Represents a processing unit in the Machine.
Describable	A component capable of describing itself.
GarbageCollectionStrategy	A garbage collection strategy, defining how the GarbageCollector is run.
GarbageCollector	This interface represents the Garbage Collector of the JVM.
HardwareComponent	A hardware component of the machine.
JVM	Represents the JVM.
JVMComponent	Interface for subcomponents of the JVM.
Machine	Represents the hardware on which the OperatingSystem and JVM is run.
Memory	Interface for components having some sort of memory.
MemorySystem	Interface to the JVM memory system.
NIC	Interface for the physical network interface components.
OperatingSystem	Representation of the Operating system.
Optimization	Deprecated. Replaced by com.bea.jvm.CodeGenerationStrategy
OptimizationLevel	Deprecated. Replaced by CodeGenerationStrategy.
PhysicalMemory	The physical memory in a Machine.
ProfilingSystem	Interface for retrieving profiling information from JRockit.
ThreadSnapshot	Interface representing a snapshot of a thread's state at a given time.
ThreadSnapshot.Monitor	Interface representing a monitor from a specific thread snapshot.
ThreadSystem	Interface to the thread system of the JVM.

Class Summary

JVMFactory	A utility class to acquire a JVM instance.
ManagementPermission	Basic security permission needed for accessing the ManagementAPI.

Exception Summary

ClassRedefinitionException	Thrown by the JRockit Management API whenever a class redefinition failed due to bad bytecode being supplied.
NoSuchThreadException	Exception thrown by various methods in the ThreadSystem interface.
NotAvailableException	Exception thrown when a certain feature isn't currently available in this JVM.
UnapplicableMethodException	Exception thrown by various parts of the ProfilingSystem whenever the method used as an argument to a method isn't applicable, either because of some modifier, or because the functionality hasn't been activated for that specific method.

Package com.bea.jvm Description

Provides the interfaces and the factory class for the JRockit management API.

Overview

JVMFactory – Provides a static method to fetch an instance of JVM. This is the starting point for working with the API.
JVM – Provides basic information about the JVM and is also the interface from which to access the different information subsystems available.

The subsystems reachable from JVM are:

• ClassLibrary – Provides a way to monitor and manage the set of currently loaded Classes and ClassLoaders.
• CompilationSystem – Provides a way to monitor and manage the way methods and constructors are compiled.
• Machine – Provides information about the hardware the JVM is running on, like CPUs, network adapters and memory.
• MemorySystem – Provides heap and garbage collection data.
• OperatingSystem – Basic information about the OS the JVM is running on.
• ProfilingSystem – Provides a way to perform lightweight profiling of the JVM, for instance invocation counting.
• ThreadSystem – Provides thread stack dumps, thread snapshots, thread counts and means to access the threads running in JRockit.

Basic usage

First you fetch a reference to an actual instance of JVM by using the JVMFactory:

	
	com.bea.jvm.JVM myJVM = com.bea.jvm.JVMFactory.getJVM();

From the JVM instance you can access the different subsystems, for instance the memory system. From the memory system you can, for example, ask for heap size information, or access the GarbageCollector. Reading the currently used heap size (in bytes) looks like this:

	com.bea.jvm.JVM myJVM = com.bea.jvm.JVMFactory.getJVM();
	long heapSize = myJVM.getMemorySystem().getUsedHeapSize();

To check if we are using a parallel garbage collector with a nursery could look like this:

	com.bea.jvm.GarbageCollector myGC = myJVM.getMemorySystem().getGarbageCollector();
	boolean isParallelWithNursery = myGC.isParallel() && myGC.isGenerational();

Since:

JRockit Viking

See Also:

com.bea.jvm