Package org.jppf.management.diagnostics

Class Diagnostics

java.lang.Object

org.jppf.management.diagnostics.Diagnostics

All Implemented Interfaces:

Closeable, AutoCloseable, DiagnosticsMBean

public class Diagnostics
extends Object
implements DiagnosticsMBean, Closeable

Implementation of the DiagnosticsMBean interface.

Author:

Laurent Cohen

Field Summary

Fields inherited from interface org.jppf.management.diagnostics.DiagnosticsMBean

MBEAN_NAME_DRIVER, MBEAN_NAME_NODE

Constructor Summary

Constructors

Constructor	Description
Diagnostics(String closeableType)	Initialize this MBean implementation.

Method Summary

Modifier and Type	Method	Description
void	close()
Double	cpuLoad()	Get an approximation of the current CPU load.
void	gc()	Perform a full garbage collection.
List<JPPFProperty<?>>	getMonitoringDataProperties()	Get the list of properties available as monitoring data.
Boolean	hasDeadlock()	Determine whether a deadlock is detected in the JVM.
HealthSnapshot	healthSnapshot()	Get a summarized snapshot of the JVM health.
String	healthSnapshotAsString()	Get a a string representation of a JVM health snapshot.
String	heapDump()	Trigger a heap dump of the JVM.
MemoryInformation	memoryInformation()	Get the current state of the heap and non-heap memory for the JVM.
ThreadDump	threadDump()	Get a full thread dump, including detection of deadlocks.
String[]	threadNames()	Get the names of all live threads in the current JVM.

Methods inherited from class java.lang.Object

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

Constructor Details

Diagnostics

public Diagnostics(String closeableType)

Initialize this MBean implementation.

Parameters:

closeableType - the name of the type of closeable to use.

Method Details

memoryInformation

public MemoryInformation memoryInformation()
                                    throws Exception

Description copied from interface: DiagnosticsMBean

Get the current state of the heap and non-heap memory for the JVM.

Specified by:

memoryInformation in interface DiagnosticsMBean

Returns:

a MemoryInformation instance.

Throws:

Exception - if any error occurs.

gc

public void gc()
        throws Exception

Description copied from interface: DiagnosticsMBean

Perform a full garbage collection. This method calls System.gc().

Specified by:

gc in interface DiagnosticsMBean

Throws:

Exception - if any error occurs.

threadNames

public String[] threadNames()
                     throws Exception

Description copied from interface: DiagnosticsMBean

Get the names of all live threads in the current JVM.

Specified by:

threadNames in interface DiagnosticsMBean

Returns:

an arrray of thread names as strings.

Throws:

Exception - if any error occurs.

threadDump

public ThreadDump threadDump()
                      throws Exception

Description copied from interface: DiagnosticsMBean

Get a full thread dump, including detection of deadlocks.

Specified by:

threadDump in interface DiagnosticsMBean

Returns:

a ThreadDump instance.

Throws:

Exception - if any error occurs.

hasDeadlock

public Boolean hasDeadlock()
                    throws Exception

Description copied from interface: DiagnosticsMBean

Determine whether a deadlock is detected in the JVM.

Specified by:

hasDeadlock in interface DiagnosticsMBean

Returns:

true if a deadlock is detected, false otherwise.

Throws:

Exception - if any error occurs.

healthSnapshot

public HealthSnapshot healthSnapshot()
                              throws Exception

Description copied from interface: DiagnosticsMBean

Get a summarized snapshot of the JVM health.

Specified by:

healthSnapshot in interface DiagnosticsMBean

Returns:

a HealthSnapshot instance.

Throws:

Exception - if any error occurs.

healthSnapshotAsString

public String healthSnapshotAsString()
                              throws Exception

Description copied from interface: DiagnosticsMBean

Get a a string representation of a JVM health snapshot. The returned string contains a set of key / value pairs separated by new lines. As such, it can be loaded directly into a Properties or TypedProperties object via their load(Reader) method, using a StringReader.

Specified by:

healthSnapshotAsString in interface DiagnosticsMBean

Returns:

a Properties-compatible string representation of a JVM health snapshot.

Throws:

Exception - if any error occurs.

heapDump

public String heapDump()
                throws Exception

Description copied from interface: DiagnosticsMBean

Trigger a heap dump of the JVM. This will not work with all JVM implementations. It should work with Oracle standard and JRockit JVMs, along with IBM JVM.

Specified by:

heapDump in interface DiagnosticsMBean

Returns:

a message describing the outcome.

Throws:

Exception - if any error occurs.

cpuLoad

public Double cpuLoad()

Description copied from interface: DiagnosticsMBean

Get an approximation of the current CPU load. The computed value is equal to sumi(thread_used_cpui) / interval, for all the live threads of the JVM at the time of the computation. Thus, errors may occur, since many threads may have been created then died between two computations. However, in most cases this is a reasonable approximation, whose computation does not tax the CPU too heavily.

Specified by:

cpuLoad in interface DiagnosticsMBean

Returns:

the cpu load as a double value in the range [0, 1] (ratio of totalCpuTime / computationInterval), or -1d if CPU time measurement is not available for the JVM.

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

getMonitoringDataProperties

public List<JPPFProperty<?>> getMonitoringDataProperties()

Description copied from interface: DiagnosticsMBean

Get the list of properties available as monitoring data.

Specified by:

getMonitoringDataProperties in interface DiagnosticsMBean

Returns:

a list of the properties described as instances of JPPFProperty.