package com.custardsource.parfait.spring;
import com.custardsource.parfait.Monitorable;
import com.custardsource.parfait.MonitorableRegistry;
import com.custardsource.parfait.MonitoringView;
import com.custardsource.parfait.QuiescentRegistryListener;
import com.google.common.collect.Lists;
import org.springframework.context.Lifecycle;
import java.util.Collection;
/**
* Adapter between a normal MonitoringView and Spring's Lifecycle interface (which conveniently has the exact-same
* methods).
*/
public class SelfStartingMonitoringView implements Lifecycle {
private final MonitoringView monitoringView;
private final MonitorableRegistry monitorableRegistry;
private Collection<Monitorable<?>> previouslySeenMonitorables = Lists.newArrayList();
private static final long DEFAULT_QUIET_PERIOD = 5000L;
private QuiescentRegistryListener quiescentRegistryListener;
private final long quietPeriodInMillis;
public SelfStartingMonitoringView(MonitoringView monitoringView) {
this(monitoringView, DEFAULT_QUIET_PERIOD);
}
public SelfStartingMonitoringView(MonitoringView monitoringView, final long quietPeriodInMillis) {
this(MonitorableRegistry.DEFAULT_REGISTRY, monitoringView, quietPeriodInMillis);
}
public SelfStartingMonitoringView(MonitorableRegistry registry, MonitoringView monitoringView) {
this(registry, monitoringView, DEFAULT_QUIET_PERIOD);
}
public SelfStartingMonitoringView(MonitorableRegistry registry, MonitoringView monitoringView, final long quietPeriodInMillis) {
this.monitoringView = monitoringView;
this.monitorableRegistry = registry;
this.quietPeriodInMillis = quietPeriodInMillis;
}
// TODO Pass in a MonitorableRegistryListener in a constructor so we can make unit tests even easier.
@Override
public void start() {
previouslySeenMonitorables = monitorableRegistry.getMonitorables();
monitoringView.startMonitoring(previouslySeenMonitorables);
this.quiescentRegistryListener = new QuiescentRegistryListener(new Runnable() {
@Override
public void run() {
stop();
start();
}
}, quietPeriodInMillis);
monitorableRegistry.addRegistryListener(quiescentRegistryListener);
}
@Override
public void stop() {
monitorableRegistry.removeRegistryListener(quiescentRegistryListener);
this.quiescentRegistryListener.stop();
monitoringView.stopMonitoring(previouslySeenMonitorables);
}
@Override
public boolean isRunning() {
return monitoringView.isRunning();
}
public static final long defaultQuietPeriod() {
return DEFAULT_QUIET_PERIOD;
}
}