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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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package org.jgroups.util;

import java.util.Map;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Consumer;
import java.util.function.Predicate;

/**
 * Collects actions by key and executes them - if a predicate is true - every N ms.
 * @author Bela Ban
 * @since  5.3.1
 */
public class Delayer {
    protected long         timeout=2000; // ms
    protected Map map=new ConcurrentHashMap<>();

    public Delayer(long timeout) {
        this.timeout=timeout;
    }

    public long       timeout()       {return timeout;}
    public Delayer timeout(long t) {timeout=t; return this;}
    public int        size()          {return map.size();}
    public int        done()          {return (int)map.values().stream().filter(Entry::done).count();}

    public Delayer add(T key, Predicate pred, Consumer action) {
        map.computeIfAbsent(key, k -> new Entry(k, pred, action).run());
        return this;
    }

    public Delayer clear() {
        map.values().forEach(e -> {
            if(e.f != null)
                e.f.cancel(true);
        });
        map.clear();
        return this;
    }

    @Override
    public String toString() {
        return String.format("%d entries (%d done)", size(), done());
    }

    protected class Entry {
        protected T                       key;
        protected Predicate            pred;
        protected Consumer       action;
        protected CompletableFuture f;

        public Entry(T key, Predicate pred, Consumer action) {
            this.key=key;
            this.pred=pred;
            this.action=action;
        }

        public boolean done() {
            return f.isDone();
        }

        public Entry run() {
            f=CompletableFuture.supplyAsync(() -> Util.waitUntilTrue(timeout, timeout / 10, () -> pred.test(key)))
              .thenAccept(success -> {
                  try {
                      action.accept(success);
                  }
                  finally {
                      map.remove(key);
                  }
              });
            return this;
        }

        @Override
        public String toString() {
            return String.format("%s: done=%b", key, done());
        }
    }
}