com.bea.jvm
Interface ThreadSystem

All Superinterfaces:

Describable, JVMComponent

public interface ThreadSystem

extends JVMComponent

Interface to the thread system of the JVM.

Author:

Calle Wilund, Marcus Hirt

Method Summary

java.util.Collection	getAllThreads() Returns a Collection of all the Threads running in the VM.
int	getDaemonThreadCount() Returns the number of daemon threads in the system.
java.lang.Thread	getThread(int id) Returns a thread matching the specified id.
java.util.Collection	getThreads(java.lang.String name) Returns a Collection with all the threads with the specified name.
ThreadSnapshot	getThreadSnapshot(int id) Get a snapshot of a thread in the JVM.
ThreadSnapshot	getThreadSnapshot(java.lang.Thread t) Get a snapshot of a thread in the JVM.
java.util.Collection	getThreadSnapshots() Returns a Collection of ThreadSnapshots for all the live threads in the JVM.
java.util.Collection	getThreadSnapshots(java.lang.String name) Gets snapshots for the threads matching the specified name.
java.lang.String	getThreadStackDump() Convenience method returning a thread stack dump for all live threads in the system.
int	getTotalThreadCount() Returns the total number of running threads in the system, including daemon threads.
boolean	isUsingThinThreads() Returns true if the thread system is using thin treads, false otherwise.

Methods inherited from interface com.bea.jvm.Describable

getDescription

Method Detail

getThreadSnapshots

public java.util.Collection getThreadSnapshots()
                                        throws NotAvailableException

Returns a Collection of ThreadSnapshots for all the live threads in the JVM. Note that when this is returned, the threads in the snapshot will have been resumed and may well have terminated.

Note: The snapshot of the threads only includes live threads. Other ones are either just newly created java objects or dead.

Returns:

ThreadSnapshots for all threads in the JVM.

Throws:

NotAvailableException - if this functionality isn't available in the JVM.

See Also:

ThreadSnapshot

getThreadSnapshot

public ThreadSnapshot getThreadSnapshot(java.lang.Thread t)
                                 throws NotAvailableException

Get a snapshot of a thread in the JVM. Note that when this is returned, the thread in the snapshot will have been resumed and may have terminated.

Parameters:

t - thread to get a snapshot for.

Returns:

the ThreadSnapshot for the specified thread.

Throws:

NotAvailableException - if this functionality isn't available in the JVM.

See Also:

ThreadSnapshot

getThreadSnapshots

public java.util.Collection getThreadSnapshots(java.lang.String name)
                                        throws NotAvailableException

Gets snapshots for the threads matching the specified name. Note that when this is returned, the threads in the snapshot will have been resumed and may well have terminated.

Parameters:

name - the name of the threads to find and get snapshots for.

Returns:

a Collection of ThreadSnapshots for all threads in the JVM matching the name parameter. Will return an empty collection if no threads matching the name could be found.

Throws:

NotAvailableException - if this functionality isn't available in the JVM.

See Also:

ThreadSnapshot

getThreadSnapshot

public ThreadSnapshot getThreadSnapshot(int id)
                                 throws NotAvailableException,
                                        NoSuchThreadException

Get a snapshot of a thread in the JVM. Note that when this is returned, the thread in the snapshot will have been resumed and may well have terminated

Parameters:

id - the id of thread to get a snapshot for.

Returns:

a ThreadSnapshot for the specified thread.

Throws:

NoSuchThreadException - if no thread matching the id can be found.

NotAvailableException - if this functionality isn't available in this JVM.

getTotalThreadCount

public int getTotalThreadCount()
                        throws NotAvailableException

Returns the total number of running threads in the system, including daemon threads.

Returns:

the total number of running threads in the system (including daemon threads).

Throws:

NotAvailableException - if this functionality isn't available in this JVM.

getDaemonThreadCount

public int getDaemonThreadCount()
                         throws NotAvailableException

Returns the number of daemon threads in the system.

Returns:

the number of daemon threads in the system.

Throws:

NotAvailableException - if this functionality isn't available in this JVM.

getAllThreads

public java.util.Collection getAllThreads()
                                   throws NotAvailableException

Returns a Collection of all the Threads running in the VM.

Returns:

a Collection of all the Threads running in the VM.

Throws:

NotAvailableException - if this functionality isn't available in this JVM.

getThreads

public java.util.Collection getThreads(java.lang.String name)
                                throws NotAvailableException

Returns a Collection with all the threads with the specified name. Will return an empty collection if no matching thread can be found.

Parameters:

name - the name of thread to find. If name is null, a NullPointerException will be thrown.

Returns:

a Collection with all the threads with the specified name. Will return an empty collection if no matching thread can be found.

Throws:

NotAvailableException - if this functionality isn't available in this JVM.

getThread

public java.lang.Thread getThread(int id)
                           throws NotAvailableException,
                                  NoSuchThreadException

Returns a thread matching the specified id.

Parameters:

id - the thread id of thread to find.

Returns:

the thread matching the specified id.

Throws:

NoSuchThreadException - if no thread matching the id can be found.

NotAvailableException - if this functionality isn't available in this JVM.

isUsingThinThreads

public boolean isUsingThinThreads()
                           throws NotAvailableException

Returns true if the thread system is using thin treads, false otherwise.

Returns:

true if the thread system is using thin treads, false otherwise.

Throws:

NotAvailableException - if this functionality isn't available in this JVM.

getThreadStackDump

public java.lang.String getThreadStackDump()
                                    throws NotAvailableException

Convenience method returning a thread stack dump for all live threads in the system. Similar to the string dumped to the console when pressing ctrl-break.

Returns:

see above.

Throws:

NotAvailableException - if this functionality isn't available in this JVM.