package io.dropwizard.metrics;
import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.util.Collections;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
/**
* A set of gauges for the JVM name, vendor, and uptime.
*/
public class JvmAttributeGaugeSet implements MetricSet {
private final RuntimeMXBean runtime;
/**
* Creates a new set of gauges.
*/
public JvmAttributeGaugeSet() {
this(ManagementFactory.getRuntimeMXBean());
}
/**
* Creates a new set of gauges with the given {@link RuntimeMXBean}.
* @param runtime JVM management interface with access to system properties
*/
public JvmAttributeGaugeSet(RuntimeMXBean runtime) {
this.runtime = runtime;
}
@Override
public Map<MetricName, Metric> getMetrics() {
final Map<MetricName, Metric> gauges = new HashMap<>();
gauges.put(MetricName.build("name"), (Gauge<String>) runtime::getName);
gauges.put(MetricName.build("vendor"), (Gauge<String>) () -> String.format(Locale.US,
"%s %s %s (%s)",
runtime.getVmVendor(),
runtime.getVmName(),
runtime.getVmVersion(),
runtime.getSpecVersion()));
gauges.put(MetricName.build("uptime"), (Gauge<Long>) runtime::getUptime);
return Collections.unmodifiableMap(gauges);
}
}