Main.java

package mm;

import java.util.UUID;

import com.hazelcast.config.ClasspathXmlConfig;
import com.hazelcast.core.Hazelcast;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.MultiMap;

public class Main {

	public static void main(String[] args) {
				
		HazelcastInstance hazelcast = Hazelcast.newHazelcastInstance(new ClasspathXmlConfig("mm.xml"));
		MultiMap<Integer, UUID> map = hazelcast.getMultiMap("mm");
		Putter putter = new Putter(map);
		Remover remover = new Remover(map);
		
		Thread putterThread = new Thread(putter);
		Thread removerThread = new Thread(remover);
		
		putterThread.start();
		removerThread.start();
		
		try {
			Thread.sleep(10000);
		} catch (InterruptedException e) {}
		
		putter.setRunning(false);
		try {
			putterThread.join();
		} catch (InterruptedException e) {}
		
		remover.setRunning(false);
		try {
			removerThread.join();
		} catch (InterruptedException e) {}
				
		try {
			Thread.sleep(2000);
		} catch (InterruptedException e) {}
		hazelcast.getLifecycleService().shutdown();
	}

}

mm.xml

<?xml version="1.0" encoding="UTF-8"?>
<hazelcast xsi:schemaLocation="http://www.hazelcast.com/schema/config hazelcast-basic.xsd"
           xmlns="http://www.hazelcast.com/schema/config"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
	<group>
        <name>mm</name>
        <password>mm</password>
    </group>
	<network>
		<port auto-increment="true">5701</port>
        <join>
            <multicast enabled="true">
                <multicast-group>224.2.2.3</multicast-group>
                <multicast-port>54327</multicast-port>
            </multicast>
        </join>
    </network>
    <multiMap name="mm"></multiMap>
</hazelcast>

Putter.java

package mm;

import java.util.Random;
import java.util.UUID;

import com.hazelcast.core.MultiMap;

public class Putter implements Runnable {

	private MultiMap<Integer, UUID> map;
	private boolean running = true;
		
	public Putter(MultiMap<Integer, UUID> map) {
		this.map = map;
	}

	public void setRunning(boolean running) {
		this.running = running;
	}

	public void run() {
		Random random = new Random();
		while(running) {
			UUID uuid = UUID.randomUUID();
			map.put(random.nextInt(10), uuid);
			try {
				Thread.sleep(random.nextInt(100));
			} catch (InterruptedException e) {}
		}
	}
	
	
}

Remover.java

package mm;

import java.util.Collection;
import java.util.Random;
import java.util.UUID;

import com.hazelcast.core.MultiMap;

public class Remover implements Runnable {

	private MultiMap<Integer, UUID> map;
	private boolean running = true;
	
	public Remover(MultiMap<Integer, UUID> map) {
		this.map = map;
	}
	
	public void setRunning(boolean running) {
		this.running = running;
	}
	
	public void run() {
		Random random = new Random();
		while(running) {
			for (int i : map.keySet()) {
				if (map.tryLock(i)) {
					Collection<UUID> uuids = map.get(i);
					if (uuids != null) {
						for (UUID uuid : uuids)
							map.remove(i, uuid);
					}					
					try {
						Thread.sleep(10);
					} catch (InterruptedException e) {}
					map.unlock(i);
				}
			}
			try {
				Thread.sleep(random.nextInt(100));
			} catch (InterruptedException e) {}
		}
	}

	
}