ItemCache.java

package com.xerox.amazonws.simpledb;

import java.util.List;

/**
 * This interface describes calls that the Domain will make into a caching
 * system. For now, only items are cached by id.
 */
public interface ItemCache {

	/**
	 * This retrieves an item from the cache. A null is returned if the item
	 * is not cachced.
	 *
	 * @param id the identifier for the item being retrieved
	 * @return the item found (or null)
	 */
	public Item getItem(String id);

	/**
	 * Stores an item in the cache.
	 *
	 * @param i the item to be stored
	 */
	public void putItem(Item i);

	/**
	 * Removes an item from the cache.
	 *
	 * @param id the identifier for the item being removed
	 */
	public void removeItem(String id);

	/**
	 * Retrieves a complete list of items in the cache
	 */
	public List<Item> itemSet();

	/**
	 * Clears the cache. This would be used to ensure only new data is being fetched.
	 */
	public void clear();
}