diff --git a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/HelperMethods.java b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/HelperMethods.java
index 9a0309f..544f896 100644
--- a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/HelperMethods.java
+++ b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/HelperMethods.java
@@ -58,8 +58,8 @@ public abstract class HelperMethods {
 	private static final String PATH_SEPARATOR = "/";
 
 	// caches
-	private static CacheInterface userEmailCache = new CacheImpl(1000 * 60 * 30);
-	private static CacheInterface userFullnameCache = new CacheImpl(1000 * 60 * 30);
+	private static CacheInterface<String, String> userEmailCache = new CacheImpl<String, String>(1000 * 60 * 30);
+	private static CacheInterface<String, String> userFullnameCache = new CacheImpl<String, String>(1000 * 60 * 30);
 
 	/**
 	 * Convert a group name to its id on ckan
@@ -132,7 +132,6 @@ public abstract class HelperMethods {
 	 * @return
 	 * @throws Exception 
 	 */
-	@SuppressWarnings("unchecked")
 	public static String getUserEmail(String context, String token){
 
 		// check in cache
@@ -156,7 +155,6 @@ public abstract class HelperMethods {
 	 * @return
 	 * @throws Exception 
 	 */
-	@SuppressWarnings("unchecked")
 	public static String getUserFullname(String context, String token){
 
 		// check in cache
diff --git a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/cache/CacheImpl.java b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/cache/CacheImpl.java
index 4e66e04..f5054a1 100644
--- a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/cache/CacheImpl.java
+++ b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/utils/cache/CacheImpl.java
@@ -10,14 +10,14 @@ import org.slf4j.LoggerFactory;
  * @author Costantino Perciante at ISTI-CNR 
  * (costantino.perciante@isti.cnr.it)
  */
-public class CacheImpl implements CacheInterface<String, Long> {
+public class  CacheImpl <K, V> implements CacheInterface<K, V> {
 
 	private static final org.slf4j.Logger logger = LoggerFactory.getLogger(CacheImpl.class);
 
 	/**
 	 * The hashmap
 	 */
-	private Map<String, CacheValueBean<Long>> userSpaceMap;
+	private Map<K, CacheValueBean<V>> userSpaceMap;
 
 	/**
 	 * Cache entry expires after EXPIRED_AFTER ms
@@ -30,10 +30,10 @@ public class CacheImpl implements CacheInterface<String, Long> {
 	}
 
 	@Override
-	public Long get(String key) {
+	public V get(K key) {
 
 		if(userSpaceMap.containsKey(key)){
-			CacheValueBean<Long> bean = userSpaceMap.get(key);
+			CacheValueBean<V> bean = userSpaceMap.get(key);
 			if(CacheUtilities.expired(bean.getTTL(), ttl)){
 				userSpaceMap.remove(key);
 				logger.debug("Amount of space in the infrastructure used expired for key " + key + ", returning null");
@@ -45,8 +45,8 @@ public class CacheImpl implements CacheInterface<String, Long> {
 	}
 
 	@Override
-	public boolean insert(String key, Long value) {
-		CacheValueBean<Long> newBean = new CacheValueBean<Long>(value, System.currentTimeMillis());
+	public boolean insert(K key, V obj) {
+		CacheValueBean<V> newBean = new CacheValueBean<V>(obj, System.currentTimeMillis());
 		userSpaceMap.put(key, newBean);
 		return true;
 	}
diff --git a/src/test/java/org/gcube/data_catalogue/grsf_publish_ws/JTests.java b/src/test/java/org/gcube/data_catalogue/grsf_publish_ws/JTests.java
index 82284a3..143eae2 100644
--- a/src/test/java/org/gcube/data_catalogue/grsf_publish_ws/JTests.java
+++ b/src/test/java/org/gcube/data_catalogue/grsf_publish_ws/JTests.java
@@ -42,6 +42,7 @@ import org.gcube.data_catalogue.grsf_publish_ws.utils.groups.Status;
 import org.gcube.data_catalogue.grsf_publish_ws.utils.threads.AssociationToGroupThread;
 import org.gcube.datacatalogue.ckanutillibrary.DataCatalogue;
 import org.gcube.datacatalogue.ckanutillibrary.DataCatalogueFactory;
+import org.junit.Test;
 import org.slf4j.LoggerFactory;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -516,4 +517,15 @@ public class JTests {
 
 
 	}
+	
+	//@Test
+	public void testCaches(){
+		
+		String context = "/gcube/devNext/NextNext";
+		String token = "";
+		for (int i = 0; i < 1000; i++) {
+			logger.debug(HelperMethods.getUserEmail(context, token));	
+		}
+		
+	}
 }