io.vertx.core.shareddata.Counter Maven / Gradle / Ivy
/*
* Copyright 2014 Red Hat, Inc.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Apache License v2.0 which accompanies this distribution.
*
* The Eclipse Public License is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* The Apache License v2.0 is available at
* http://www.opensource.org/licenses/apache2.0.php
*
* You may elect to redistribute this code under either of these licenses.
*/
package io.vertx.core.shareddata;
import io.vertx.codegen.annotations.VertxGen;
import io.vertx.core.AsyncResult;
import io.vertx.core.Handler;
/**
* An asynchronous counter that can be used to across the cluster to maintain a consistent count.
*
*
*
* @author Tim Fox
*/
@VertxGen
public interface Counter {
/**
* Get the current value of the counter
*
* @param resultHandler handler which will be passed the value
*/
void get(Handler> resultHandler);
/**
* Increment the counter atomically and return the new count
*
* @param resultHandler handler which will be passed the value
*/
void incrementAndGet(Handler> resultHandler);
/**
* Increment the counter atomically and return the value before the increment.
*
* @param resultHandler handler which will be passed the value
*/
void getAndIncrement(Handler> resultHandler);
/**
* Decrement the counter atomically and return the new count
*
* @param resultHandler handler which will be passed the value
*/
void decrementAndGet(Handler> resultHandler);
/**
* Add the value to the counter atomically and return the new count
*
* @param value the value to add
* @param resultHandler handler which will be passed the value
*/
void addAndGet(long value, Handler> resultHandler);
/**
* Add the value to the counter atomically and return the value before the add
*
* @param value the value to add
* @param resultHandler handler which will be passed the value
*/
void getAndAdd(long value, Handler> resultHandler);
/**
* Set the counter to the specified value only if the current value is the expectec value. This happens
* atomically.
*
* @param expected the expected value
* @param value the new value
* @param resultHandler the handler will be passed true on success
*/
void compareAndSet(long expected, long value, Handler> resultHandler);
}