/*
 * Licensed to Elasticsearch B.V. under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. 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.logstash.instrument.metrics;


import com.fasterxml.jackson.annotation.JsonValue;

import java.util.Objects;

/**
 * Abstract implementation of a {@link Metric}. All metrics should subclass this.
 *
 * @param <T> The underlying type for this metric. For example {@link Long} for Counter, or {@link String} for Gauge.
 */
public abstract class AbstractMetric<T> implements Metric<T> {
    final protected String name;

    /**
     * Constructor
     *
     * @param name The name of this metric. This value may be used for display purposes.
     */
    protected AbstractMetric(final String name) {
        this.name = name;
    }

    @JsonValue
    public abstract T getValue();

    @Override
    public String toString() {
        return String.format("%s -  name: %s value:%s", this.getClass().getName(), this.name, Objects.requireNonNullElse(getValue(),"null"));
    }

    @Override
    public String getName() {
        return this.name;
    }

}
