com.hazelcast.internal.util.counters.Counter Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2024, Hazelcast, Inc. All Rights Reserved.
*
* 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.hazelcast.internal.util.counters;
/**
* A Counter keeps track of a long value.
*
* It depends on the counter if increments are thread-safe.
*
* The get is thread-safe in the sense that it will see a recently published value. It doesn't mean that it
* will see the most recently published value.
*/
public interface Counter {
/**
* Gets the current value of the counter.
*
* @return the current value of the counter.
*/
long get();
/**
* Sets the current value of the counter.
*/
void set(long value);
/**
* Sets the current value of the counter
* and returns the old value.
*
* @param newValue the new value.
* @return the old value of the counter.
*/
long getAndSet(long newValue);
/**
* Increments the counter by one.
*
* @return the new counter state
*/
long inc();
/**
* Increments (or decrements) the counter by the given amount.
*
* If the amount is negative, the counter is decremented.
*
* @param amount the amount to increase or decrease the counter with.
* @return the new counter state
*/
long inc(long amount);
}