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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.concurrent.ConcurrentLinkedQueue;


/**
 * A bounded subclass of LinkedList, oldest elements are removed once max capacity is exceeded. Note that this
 * class is not synchronized (like LinkedList). Don't use this for high performance, as size() has a linear cost. But
 * in most scenarios, this class is used for maintaining a history, e.g. of digests or views, so perf is not critical.
 * @author Bela Ban Nov 20, 2003
 */
public class BoundedList extends ConcurrentLinkedQueue {
    int max_capacity=10;


    public BoundedList() {
        super();
    }

    public BoundedList(int size) {
        super();
        max_capacity=size;
    }


    /**
     * Adds an element at the tail. Removes an object from the head if capacity is exceeded
     * @param obj The object to be added
     */
    public boolean add(T obj) {
        if(obj == null) return false;
        while(size() >= max_capacity && size() > 0) {
            poll();
        }
        return super.add(obj);
    }

    public boolean addIfAbsent(T obj) {
        return obj != null && !contains(obj) && add(obj);
    }



    public T removeFromHead() {
        return poll();
    }


}