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Implementation of gaedo mechanisms backed by blueprints graph layer

There is a newer version: 1.0.16

package com.dooapp.gaedo.blueprints;

import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import java.util.Map;
import java.util.WeakHashMap;

import javax.persistence.CascadeType;

/**
 * A cache implementation, that should allow less memory consumption of gaedo
 * @author ndx
 *
 */
public class ObjectCache {
	/**
	 * Interface used to load value on cache miss.
	 * @author ndx
	 *
	 */
	public static interface ValueLoader {
		/**
		 * Get the value to load
		 * @return
		 */
		Object get();

	}
	private Map> cache = new WeakHashMap>();

	/**
	 * Create objet cache for the given cascade type
	 * TODO optimize heavily by using threadlocal and a map of cascade types to obejct caches (or a better cache implementation)
	 * @param merge
	 * @return
	 */
	public static ObjectCache create(CascadeType merge) {
		return new ObjectCache();
	}

	/**
	 * Get loaded value.
	 * This method get value from cache and, if none is found, load it using the provided {@link ValueLoader}
	 * @param objectVertexId
	 * @param valueLoader
	 * @return
	 */
	public Object get(String objectVertexId, ValueLoader valueLoader) {
		Object returned = get(objectVertexId);
		if(returned==null) {
			returned = valueLoader.get();
			put(objectVertexId, returned);
		}
		return returned;
	}

	public Object get(String objectVertexId) {
		Reference