}

    /**
     * Add an object as an attribute to the entity.
     * @param key the key of the attribute
     * @param value the value to store
     */
    public void setAttribute(final String key, final Object value)
    {
        if (this.attributes == null)
            this.attributes = new LinkedHashMap<>();
        this.attributes.put(key, value);
    }

    /**
     * Retrieve a typed object attribute value.
     * @param key the id of the attribute
     * @param clazz Class&lt;VT&gt; the class of the object to return
     * @return the stored value
     * @param <VT> the class of the attribute value to return
     */
    @SuppressWarnings("unchecked")
    public <VT> VT getAttribute(final String key, final Class<VT> clazz)
    {
        if (this.attributes == null)
            return null;
        return (VT) this.attributes.get(key);
    }

    /**
     * Retrieve an object attribute value.
     * @param key the id of the attribute
     * @return the stored value
     */
    public Object getAttribute(final String key)
    {
        return getAttribute(key, Object.class);
    }

    /**
     * Add a String as an attribute to the entity.
     * @param key the key of the attribute
     * @param value the value to store
     */
    public void setStringAttribute(final String key, final String value)
    {
        setAttribute(key, value);
    }

    /**
     * Retrieve a stored String attribute value.
     * @param key the id of the attribute
     * @return the stored value
     */
    public String getStringAttribute(final String key)
    {
        if (this.attributes == null)
            return null;
        return this.attributes.get(key).toString();
    }

    /**
     * Add a Number as an attribute to the entity.
     * @param key the key of the attribute
     * @param value the value to store
     */
    public void setNumberAttribute(final String key, final Number value)
    {
        setAttribute(key, value);
    }

    /**
     * Retrieve a stored Number attribute value.
     * @param key the id of the attribute
     * @return the stored value
     */
    public Number getNumberAttribute(final String key)
    {
        return getAttribute(key, Number.class);
    }

    /**
     * Return the creation time.
     * @return the creation time
     */
    public T getCreationTime()

final Resource.DoubleCapacity<T> resource)
        {
            for (StoredEntity<T> storedEntity : this.storage)
            {
                if (storedEntity.entity().equals(entity))
                {
                    synchronized (this.storage)
                    {
                        this.storage.remove(storedEntity);
                    }
                    this.fireTimedEvent(Seize.NUMBER_STORED_EVENT, this.storage.size(), getSimulator().getSimulatorTime());
                    T delay = SimTime.minus(getSimulator().getSimulatorTime(), storedEntity.storeTime());
                    this.fireTimedEvent(Seize.STORAGE_TIME_EVENT, delay.doubleValue(), getSimulator().getSimulatorTime());
                    this.releaseEntity(storedEntity.entity());
                    return;
                }
            }
        }
    }