clients/src/main/java/org/apache/kafka/common/metrics/MetricsReporter.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE
 * file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file
 * to You 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.apache.kafka.common.metrics;

import java.util.List;

import org.apache.kafka.common.Configurable;

/**
 * A plugin interface to allow things to listen as new metrics are created so they can be reported.
 */
public interface MetricsReporter extends Configurable {

    /**
     * This is called when the reporter is first registered to initially register all existing metrics
     * @param metrics All currently existing metrics
     */
    public void init(List<KafkaMetric> metrics);

    /**
     * This is called whenever a metric is updated or added
     * @param metric
     */
    public void metricChange(KafkaMetric metric);

    /**
     * This is called whenever a metric is removed
     * @param metric
     */
    public void metricRemoval(KafkaMetric metric);

    /**
     * Called when the metrics repository is closed.
     */
    public void close();

}