/*
* Copyright 2012-2013 the original author or authors.
*
* 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 org.springframework.boot.actuate.metrics.reader;
import org.springframework.boot.actuate.metrics.Metric;
/**
* A simple reader interface used to interrogate {@link Metric}s.
*
* @author Dave Syer
*/
public interface MetricReader {
/**
* Find an instance of the metric with the given name (usually the latest recorded
* value).
* @param metricName the name of the metric to find
* @return a metric value or null if there are none with that name
*/
Metric<?> findOne(String metricName);
/**
* Find all the metrics known to this reader.
* @return all instances of metrics known to this reader
*/
Iterable<Metric<?>> findAll();
/**
* The number of metrics known to this reader.
* @return the number of metrics
*/
long count();
}