Module com.microsoft.gctoolkit.api

Package com.microsoft.gctoolkit.jvm

Class AbstractJavaVirtualMachine

java.lang.Object

com.microsoft.gctoolkit.jvm.AbstractJavaVirtualMachine

All Implemented Interfaces:

JavaVirtualMachine

Direct Known Subclasses:

PreUnifiedJavaVirtualMachine, UnifiedJavaVirtualMachine

public abstract class AbstractJavaVirtualMachine
extends Object
implements JavaVirtualMachine

The base implementation of JavaVirtualMachine that uses the message API to feed lines to the parser(s) and post events to the aggregators.

Constructor Summary

Constructors

Constructor	Description
AbstractJavaVirtualMachine()

Method Summary

Modifier and Type	Method	Description
void	analyze(List<Aggregator<? extends Aggregation>> registeredAggregators, JVMEventChannel eventBus, DataSourceChannel dataSourceBus)	Orchestrate the analysis of a GC log.
<T extends Aggregation> Optional<T>	getAggregation(Class<T> aggregationClass)	Return the Aggregation that was used in the analysis of the GC log file that is the same class as aggregationClass.
String	getCommandLine()	Return the command line used to run the JVM, if available.
DateTimeStamp	getEstimatedJVMStartTime()	If the first event is significantly distant from zero in relation to the time intervals between the of the next N events, where N maybe 1, then this is likely a log fragment and not the start of the run.
DateTimeStamp	getJVMTerminationTime()	JVM termination time will be one of either, the time stamp in the termination event if present or, the time of the last event + that events duration.
double	getRuntimeDuration()	Return the runtime duration.
DateTimeStamp	getTimeOfFirstEvent()	Return the time of the first event in the GC log file.
boolean	isCMS()	Return true if the JVM was using CMS GC.
boolean	isG1GC()	Return true if the JVM was using G1GC.
boolean	isParallel()	Return true if the JVM was using Parallel GC.
boolean	isSerial()	Return true if the JVM was using Serial GC.
boolean	isShenandoah()	Return true if the JVM was using Shenandoah.
boolean	isZGC()	Return true if the JVM was using ZGC.
void	setDataSource(DataSource logFile)	Sets the data source
void	setEstimatedJVMStartTime(DateTimeStamp estimatedStartTime)	Sets the estimated start time as calculated by the Aggregation class

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.microsoft.gctoolkit.jvm.JavaVirtualMachine

accepts, isUnifiedLogging

Constructor Detail

AbstractJavaVirtualMachine

public AbstractJavaVirtualMachine()

Method Detail

setDataSource

public void setDataSource(DataSource logFile)
                   throws IOException

Sets the data source

Parameters:

logFile - is the source of GC logging data

Throws:

IOException - if there is any issues reading from the data source.

isG1GC

public boolean isG1GC()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using G1GC.

Specified by:

isG1GC in interface JavaVirtualMachine

Returns:

true if the GC is G1GC.

isZGC

public boolean isZGC()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using ZGC.

Specified by:

isZGC in interface JavaVirtualMachine

Returns:

true if the GC is ZGC.

isShenandoah

public boolean isShenandoah()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using Shenandoah.

Specified by:

isShenandoah in interface JavaVirtualMachine

Returns:

true if the GC is Shenandoah.

isParallel

public boolean isParallel()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using Parallel GC.

Specified by:

isParallel in interface JavaVirtualMachine

Returns:

true if the GC is Parallel GC.

isSerial

public boolean isSerial()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using Serial GC.

Specified by:

isSerial in interface JavaVirtualMachine

Returns:

true if the GC is Serial GC.

isCMS

public boolean isCMS()

Description copied from interface: JavaVirtualMachine

Return true if the JVM was using CMS GC.

Specified by:

isCMS in interface JavaVirtualMachine

Returns:

true if the GC is CMS GC.

getCommandLine

public String getCommandLine()

Description copied from interface: JavaVirtualMachine

Return the command line used to run the JVM, if available.

Specified by:

getCommandLine in interface JavaVirtualMachine

Returns:

The command line used to run the JVM, or null

getTimeOfFirstEvent

public DateTimeStamp getTimeOfFirstEvent()

Description copied from interface: JavaVirtualMachine

Return the time of the first event in the GC log file.

Specified by:

getTimeOfFirstEvent in interface JavaVirtualMachine

Returns:

The time of the last event.

getEstimatedJVMStartTime

public DateTimeStamp getEstimatedJVMStartTime()

If the first event is significantly distant from zero in relation to the time intervals between the of the next N events, where N maybe 1, then this is likely a log fragment and not the start of the run.

Try to estimate the time at which the JVM started. For log fragments, this will be the time of the first event in the log. Otherwise it will be 0.000 seconds.

Specified by:

getEstimatedJVMStartTime in interface JavaVirtualMachine

Returns:

DateTimeStamp as estimated start time.

setEstimatedJVMStartTime

public void setEstimatedJVMStartTime(DateTimeStamp estimatedStartTime)

Sets the estimated start time as calculated by the Aggregation class

Parameters:

estimatedStartTime - as calculated from observations of the event timing in the gc log.

getJVMTerminationTime

public DateTimeStamp getJVMTerminationTime()

JVM termination time will be one of either, the time stamp in the termination event if present or, the time of the last event + that events duration.

Specified by:

getJVMTerminationTime in interface JavaVirtualMachine

Returns:

DateTimeStamp

getRuntimeDuration

public double getRuntimeDuration()

Description copied from interface: JavaVirtualMachine

Return the runtime duration. This is not necessarily the difference between the first and last event. Rather, this calculation considers the duration of the events.

Specified by:

getRuntimeDuration in interface JavaVirtualMachine

Returns:

The runtime duration that the GC log represents.

getAggregation

public <T extends Aggregation> Optional<T> getAggregation(Class<T> aggregationClass)

Description copied from interface: JavaVirtualMachine

Return the Aggregation that was used in the analysis of the GC log file that is the same class as aggregationClass. In other words, aggregationClass is a key used to look up an instance of the Aggregation. The return value may be null if the Aggregation was not used in the analysis. Which Aggregations are used depends on the GC.

Specified by:

getAggregation in interface JavaVirtualMachine

Type Parameters:

T - type cast for the Aggregation class type.

Parameters:

aggregationClass - The class of the Aggregation to be returned.

Returns:

an Aggregation whose getClass() == aggregationClass, or null if given aggregationClass is not available.

analyze

public void analyze(List<Aggregator<? extends Aggregation>> registeredAggregators,
                    JVMEventChannel eventBus,
                    DataSourceChannel dataSourceBus)

Orchestrate the analysis of a GC log. Step wise 1. find the aggregators that aggregate events generated by the gc log 2. Register the aggregators with the message bus. Setup a callback so the message framework. 3. Stream the data to a publisher 4. Wait until all the aggregators have completed 5. Set the start and end times 6. Return to the caller

Specified by:

analyze in interface JavaVirtualMachine

Parameters:

registeredAggregators - all of the aggregations loaded by the module SPI

eventBus - the bus to publish events on

dataSourceBus - the bus that raw log lines are published on