com.netflix.servo.publish.BaseMetricPoller Maven / Gradle / Ivy
/*
* Copyright 2014 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.netflix.servo.publish;
import com.netflix.servo.Metric;
import com.netflix.servo.util.Preconditions;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;
/**
* Base class for simple pollers that do not benefit from filtering in advance.
* Sub-classes implement {@link #pollImpl} to return a list and all filtering
* will be taken care of by the provided implementation of {@link #poll}.
*/
public abstract class BaseMetricPoller implements MetricPoller {
protected final Logger logger = LoggerFactory.getLogger(getClass());
/**
* Return a list of all current metrics for this poller.
*/
public abstract List pollImpl(boolean reset);
/**
* {@inheritDoc}
*/
public final List poll(MetricFilter filter) {
return poll(filter, false);
}
/**
* {@inheritDoc}
*/
public final List poll(MetricFilter filter, boolean reset) {
Preconditions.checkNotNull(filter, "filter");
List metrics = pollImpl(reset);
List retained = metrics.stream().filter(m -> filter.matches(m.getConfig()))
.collect(Collectors.toList());
logger.debug("received {} metrics, retained {} metrics", metrics.size(), retained.size());
return Collections.unmodifiableList(retained);
}
}