/*
* 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.samza.metrics;
import java.util.concurrent.atomic.AtomicLong;
/**
* A counter is a {@link org.apache.samza.metrics.Metric} that represents a cumulative value.
* For example, the number of messages processed since the container was started.
*/
public class Counter implements Metric {
private final String name;
private final AtomicLong count;
public Counter(String name) {
this.name = name;
this.count = new AtomicLong(0);
}
public long inc() {
return inc(1);
}
public long inc(long n) {
return count.addAndGet(n);
}
public long dec() {
return dec(1);
}
public long dec(long n) {
return count.addAndGet(0 - n);
}
public void set(long n) {
count.set(n);
}
public void clear() {
count.set(0);
}
public long getCount() {
return count.get();
}
public String getName() {
return name;
}
public void visit(MetricsVisitor visitor) {
visitor.counter(this);
}
public String toString() {
return count.toString();
}
}