factory class added

git-svn-id: https://svn.d4science.research-infrastructures.eu/gcube/trunk/data-catalogue/ckan-util-library@130932 82a268e6-3cf1-43bd-a215-b396298e98cf

src/main/java/org/gcube/datacatalogue/ckanutillibrary/CkanUtilsFactory.java

@@ -0,0 +1,65 @@
+package org.gcube.datacatalogue.ckanutillibrary;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Please invoke this method to retrieve an object of this kind per scope.
+ * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
+ */
+public class CkanUtilsFactory {
+	
+	private static final Logger logger = LoggerFactory.getLogger(CkanUtilsFactory.class);
+	private static final long MAX_LIFETIME = 1000 * 60 * 5; // 5 MINUTES
+	private static CkanUtilsFactory instance = new CkanUtilsFactory();
+	private static ConcurrentHashMap<String, CacheBean> cache;
+	
+	private class CacheBean{
+		CKanUtilsImpl utils;
+		long ttl;
+		
+		public CacheBean(long ttl, CKanUtilsImpl utils){
+			this.ttl = ttl;
+			this.utils = utils;
+		}
+	}
+	
+	private CkanUtilsFactory(){
+		
+		logger.debug("Ckan factory object build");
+		cache = new ConcurrentHashMap<String, CacheBean>(); 
+		
+	}
+	
+	/**
+	 * Get the factory instance
+	 * @return
+	 */
+	public static CkanUtilsFactory getFactory(){
+		logger.debug("Factory requested");
+		return instance;
+	} 
+	
+	public CKanUtilsImpl getUtilsPerScope(String scope) throws Exception{
+		if(scope == null || scope.isEmpty())
+			throw new IllegalArgumentException("Invalid scope given!");
+		
+		if(cache.containsKey(scope) && !expired(cache.get(scope))){
+			return cache.get(scope).utils;
+		}
+		else{
+			logger.debug("Creating utils for scope " + scope);
+			CKanUtilsImpl utils = new CKanUtilsImpl(scope);
+			cache.put(scope, new CacheBean(System.currentTimeMillis(), utils));
+			return utils;
+		}
+	}
+
+	private boolean expired(CacheBean cacheBean) {
+		boolean expired = (cacheBean.ttl + MAX_LIFETIME <= System.currentTimeMillis());
+		logger.debug("expired is " + expired);
+		return expired;
+	}
+}

src/test/java/org/gcube/datacatalogue/ckanutillibrary/TestCKanLib.java

@@ -18,6 +18,25 @@ public class TestCKanLib {
 
 	CKanUtilsImpl instance;
 
+	//@Test
+	public void factoryTest() throws Exception{
+
+		CkanUtilsFactory factory = CkanUtilsFactory.getFactory();
+
+		while(true){
+			factory.getUtilsPerScope("/gcube");
+			Thread.sleep(60* 1000 * 3);
+			factory.getUtilsPerScope("/gcube");
+			break;
+		}
+
+		for (int i = 0; i < 5; i++) {
+			Thread.sleep(1000);
+			factory.getUtilsPerScope("/gcube");
+		}
+
+	}
+
 	//@Test
 	public void before() throws Exception{