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Feature-rich CPU affinity for the JVM - Concurrent extensions

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package org.sheinbergon.needle.concurrent.util;

import org.apache.commons.lang3.math.NumberUtils;

import java.util.concurrent.CountDownLatch;

public final class ResettableOneOffLatch {

    /**
     * Underlying mutable {@code CountDownLatch} used to provide latch synchronization facility.
     */
    private volatile CountDownLatch latch;

    /**
     * Initializes this latch in an 'unlatched' mode.
     */
    public ResettableOneOffLatch() {
        this(false);
    }

    /**
     * Initializes this latch in either 'latched' or 'unlatched' mode.
     *
     * @param latched Setting this to {@code true} instantiates this class in a 'latched' mode,
     *                requiring an initial call to {@link ResettableOneOffLatch#fire()} in order to unlatch
     */
    public ResettableOneOffLatch(final boolean latched) {
        latch = new CountDownLatch(latched ? NumberUtils.INTEGER_ONE : NumberUtils.INTEGER_ZERO);
    }

    /**
     * Reset this latch back to a 'latched' state, irregardless of its current state.
     */
    public void reset() {
        latch = new CountDownLatch(NumberUtils.INTEGER_ONE);
    }

    /**
     * Unlatches this latch, moving it to an unlatched mode.
     */
    public void fire() {
        latch.countDown();
    }

    /**
     * Wait for this latch to fire, optionally resetting it fires.
     *
     * @param reset whether or not to reset this latch after it fires
     */
    public synchronized void await(final boolean reset) {
        try {
            latch.await();
            if (reset) {
                reset();
            }
        } catch (InterruptedException iex) {
            throw new RuntimeException(iex);
        }
    }
}