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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.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;

/** Cache which maintains timestamps for keys, and methods to remove/replace expired keys. Compared to {@link AgeOutCache},
 * ExpiryCache doesn't require a timer task to run
 * @author  Bela Ban
 * @version 3.3
 */
public class ExpiryCache {
    protected long                        timeout; // in nanoseconds

    // Maintains keys and timestamps (in nanoseconds)
    protected final ConcurrentMap map=new ConcurrentHashMap<>();

    /**
     * Creates a new instance
     * @param timeout Timeout in ms
     */
    public ExpiryCache(long timeout) {
        setTimeout(timeout);
    }

    public long getTimeout() {return TimeUnit.MILLISECONDS.convert(timeout, TimeUnit.NANOSECONDS);}

    public void setTimeout(long timeout) {this.timeout=TimeUnit.NANOSECONDS.convert(timeout, TimeUnit.MILLISECONDS);}


    public boolean addIfAbsentOrExpired(K key) {
        Long val=map.get(key);
        if(val == null)
            return map.putIfAbsent(key, System.nanoTime()) == null;
        long current_time=System.nanoTime();
        return hasExpired(val, current_time) && map.replace(key, val, current_time);
    }

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

    public boolean hasExpired(K key) {
        Long val=map.get(key);
        return val == null || hasExpired(val, System.nanoTime());
    }

    public void remove(K key) {
        map.remove(key);
    }

    public void removeAll(Collection keys) {
        map.keySet().removeAll(keys);
    }


    public int removeExpiredElements() {
        int removed=0;
        long current_time=System.nanoTime();
        for(Map.Entry entry: map.entrySet()) {
            Long val=entry.getValue();
            if(val == null || hasExpired(val, current_time)) {
                map.remove(entry.getKey());
                removed++;
            }
        }
        return removed;
    }

    public void clear() {
        map.clear();
    }

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

    public String toString() {
        StringBuilder sb=new StringBuilder();
        long current_time=System.nanoTime();
        for(Map.Entry entry: map.entrySet()) {
            sb.append(entry.getKey()).append(": (age: ");
            long val=entry.getValue(); // timestamp in ns
            long age=TimeUnit.MILLISECONDS.convert(current_time - val, TimeUnit.NANOSECONDS); // ms
            if(age< 1000L)
                sb.append(age).append(" ms)");
            else
                sb.append(TimeUnit.SECONDS.convert(age, TimeUnit.MILLISECONDS)).append(" secs");
            sb.append("\n");
        }
        return sb.toString();
    }


    protected boolean hasExpired(long val, long current_time) {
        return current_time - val > timeout;
    }
}