Example usage for java.util.concurrent.atomic AtomicLongFieldUpdater compareAndSet

Introduction

In this page you can find the example usage for java.util.concurrent.atomic AtomicLongFieldUpdater compareAndSet.

Prototype

public abstract boolean compareAndSet(T obj, long expect, long update);

Source Link

Document

Atomically sets the field of the given object managed by this updater to the given updated value if the current value == the expected value.

Usage

From source file:Main.java

public static <T> long getAndAddRequest(AtomicLongFieldUpdater<T> requested, T object, long n) {
    long current;
    long next;/*from  w w  w. ja va  2  s  . c  o  m*/
    do {
        current = requested.get(object);
        next = current + n;
        if (next < 0) {
            next = Long.MAX_VALUE;
        }
    } while (!requested.compareAndSet(object, current, next));
    return current;
}

---

From source file:Main.java

/**
 * Adds {@code n} to {@code requested} field and returns the value prior to
 * addition once the addition is successful (uses CAS semantics). If
 * overflows then sets {@code requested} field to {@code Long.MAX_VALUE}.
 * /*from   w w w. j av a2 s. co m*/
 * @param <T> the type of the target object on which the field updater operates
 * 
 * @param requested
 *            atomic field updater for a request count
 * @param object
 *            contains the field updated by the updater
 * @param n
 *            the number of requests to add to the requested count
 * @return requested value just prior to successful addition
 * @deprecated Android has issues with reflection-based atomics
 */
@Deprecated
public static <T> long getAndAddRequest(AtomicLongFieldUpdater<T> requested, T object, long n) {
    // add n to field but check for overflow
    while (true) {
        long current = requested.get(object);
        long next = addCap(current, n);
        if (requested.compareAndSet(object, current, next)) {
            return current;
        }
    }
}

---

From source file:Main.java

static <T> long getAndAddRequest(AtomicLongFieldUpdater<T> paramAtomicLongFieldUpdater, T paramT,
        long paramLong) {
    long l1;//from   w  w  w  .j a va2  s .co  m
    long l2;
    do {
        l1 = paramAtomicLongFieldUpdater.get(paramT);
        l2 = l1 + paramLong;
        if (l2 < 0L)
            l2 = 9223372036854775807L;
    } while (!paramAtomicLongFieldUpdater.compareAndSet(paramT, l1, l2));
    return l1;
}

---