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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS 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.Collection;
import java.util.Map;
import java.util.concurrent.*;

/** Cache which removes its elements after a certain time
 * @author Bela Ban
 */
public class AgeOutCache {
    private final TimeScheduler           timer;
    private long                          timeout;
    private final ConcurrentMap map=new ConcurrentHashMap<>();
    private Handler                       handler;

    public interface Handler {
        void expired(K key);
    }


    public AgeOutCache(TimeScheduler timer, long timeout) {
        this.timer=timer;
        this.timeout=timeout;
    }

    public AgeOutCache(TimeScheduler timer, long timeout, Handler handler) {
        this(timer, timeout);
        this.handler=handler;
    }

    public long getTimeout() {
        return timeout;
    }

    public void setTimeout(long timeout) {
        this.timeout=timeout;
    }

    public Handler getHandler() {
        return handler;
    }

    public void setHandler(Handler handler) {
        this.handler=handler;
    }

    public void add(final K key) {
        Future future=timer.schedule(new Runnable() {
            public void run() {
                if(handler != null) {
                    try {
                        handler.expired(key);
                    }
                    catch(Throwable t) {
                    }
                }
                Future tmp=map.remove(key);
                if(tmp != null)
                    tmp.cancel(true);
            }

            public String toString() {
                return "AgeOutCache (timeout=" + timeout +
                  ", handler=" + (handler != null? handler.getClass().getSimpleName() : null) + ")";
            }
        }, timeout, TimeUnit.MILLISECONDS, false); // this task never blocks
        Future result=map.putIfAbsent(key, future);
        if(result != null)
            future.cancel(true);
    }

    public boolean contains(K key) {
        return key != null && map.containsKey(key);
    }

    public void remove(K key) {
        Future future=map.remove(key);
        if(future != null)
            future.cancel(true);
    }

    public void removeAll(Collection keys) {
        if(keys != null)
            keys.forEach(this::remove);
    }

    public void clear() {
        for(Future future: map.values())
            future.cancel(true);
        map.clear();
    }

    public int size() {
        return map.size();
    }

    public String toString() {
        StringBuilder sb=new StringBuilder();
        for(Map.Entry entry: map.entrySet()) {
            sb.append(entry.getKey()).append(": ").append(entry.getValue()).append("\n");
        }
        return sb.toString();
    }
}