io.pcp.parfait

Class PollingMonitoredValue<T>

java.lang.Object

io.pcp.parfait.AbstractMonitorable<T>

io.pcp.parfait.SettableValue<T>

io.pcp.parfait.PollingMonitoredValue<T>

All Implemented Interfaces:

Monitorable<T>

public class PollingMonitoredValue<T>
extends SettableValue<T>

Monitors the value returned by calls at the provided interval to the provided Supplier.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private class	PollingMonitoredValue.PollerTask

Field Summary

Fields

Modifier and Type	Field and Description
private static org.slf4j.Logger	LOG
private static int	MIN_UPDATE_INTERVAL The minimum time in ms that may be specified as an updateInterval.
private com.google.common.base.Supplier<T>	poller
private static java.util.Timer	POLLING_TIMER
private static java.util.List<java.util.TimerTask>	SCHEDULED_TASKS All timer tasks that have been scheduled in PollingMonitoredValues; useful only for testing.
private static Scheduler	SHARED_TIMER_SCHEDULER

Fields inherited from class io.pcp.parfait.SettableValue

value

Constructor Summary

Constructors

Constructor and Description
PollingMonitoredValue(java.lang.String name, java.lang.String description, MonitorableRegistry registry, int updateInterval, com.google.common.base.Supplier<T> poller, ValueSemantics semantics) Creates a new PollingMonitoredValue with the specified polling interval.
PollingMonitoredValue(java.lang.String name, java.lang.String description, MonitorableRegistry registry, int updateInterval, com.google.common.base.Supplier<T> poller, ValueSemantics semantics, javax.measure.Unit<?> unit) Creates a new PollingMonitoredValue with the specified polling interval.
PollingMonitoredValue(java.lang.String name, java.lang.String description, MonitorableRegistry registry, int updateInterval, com.google.common.base.Supplier<T> poller, ValueSemantics semantics, javax.measure.Unit<?> unit, Scheduler scheduler) Creates a new PollingMonitoredValue with the specified polling interval.

Method Summary

Modifier and Type	Method and Description
static <T> void	poll(java.lang.String name, java.lang.String description, MonitorableRegistry registry, int updateInterval, com.google.common.base.Supplier<T> poller, ValueSemantics semantics, javax.measure.Unit<?> unit) Convenient factory method to create pollers you don't care about keeping – that is, pollers which should be registered and start updating their value, but which you don't need to hold a reference to (because you will presumably just be modifying the polled source).
(package private) static void	runAllTasks()

Methods inherited from class io.pcp.parfait.SettableValue

get, set

Methods inherited from class io.pcp.parfait.AbstractMonitorable

attachMonitor, getDescription, getName, getSemantics, getType, getUnit, isAttached, logValue, notifyMonitors, registerSelf, removeMonitor

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final org.slf4j.Logger LOG

MIN_UPDATE_INTERVAL

private static final int MIN_UPDATE_INTERVAL

The minimum time in ms that may be specified as an updateInterval.

See Also:

Constant Field Values

POLLING_TIMER

private static final java.util.Timer POLLING_TIMER

SHARED_TIMER_SCHEDULER

private static Scheduler SHARED_TIMER_SCHEDULER

poller

private final com.google.common.base.Supplier<T> poller

SCHEDULED_TASKS

private static final java.util.List<java.util.TimerTask> SCHEDULED_TASKS

All timer tasks that have been scheduled in PollingMonitoredValues; useful only for testing.

Constructor Detail

PollingMonitoredValue

public PollingMonitoredValue(java.lang.String name,
                             java.lang.String description,
                             MonitorableRegistry registry,
                             int updateInterval,
                             com.google.common.base.Supplier<T> poller,
                             ValueSemantics semantics)

Creates a new PollingMonitoredValue with the specified polling interval.

Parameters:

updateInterval - how frequently the Poller should be checked for updates (may not be less than MIN_UPDATE_INTERVAL

PollingMonitoredValue

public PollingMonitoredValue(java.lang.String name,
                             java.lang.String description,
                             MonitorableRegistry registry,
                             int updateInterval,
                             com.google.common.base.Supplier<T> poller,
                             ValueSemantics semantics,
                             javax.measure.Unit<?> unit)

Creates a new PollingMonitoredValue with the specified polling interval.

Parameters:

updateInterval - how frequently the Poller should be checked for updates (may not be less than MIN_UPDATE_INTERVAL

PollingMonitoredValue

public PollingMonitoredValue(java.lang.String name,
                             java.lang.String description,
                             MonitorableRegistry registry,
                             int updateInterval,
                             com.google.common.base.Supplier<T> poller,
                             ValueSemantics semantics,
                             javax.measure.Unit<?> unit,
                             Scheduler scheduler)

Creates a new PollingMonitoredValue with the specified polling interval.

Parameters:

updateInterval - how frequently the Poller should be checked for updates (may not be less than MIN_UPDATE_INTERVAL

Method Detail

runAllTasks

static void runAllTasks()

poll

public static <T> void poll(java.lang.String name,
                            java.lang.String description,
                            MonitorableRegistry registry,
                            int updateInterval,
                            com.google.common.base.Supplier<T> poller,
                            ValueSemantics semantics,
                            javax.measure.Unit<?> unit)

Convenient factory method to create pollers you don't care about keeping – that is, pollers which should be registered and start updating their value, but which you don't need to hold a reference to (because you will presumably just be modifying the polled source).