diff --git a/.classpath b/.classpath
index 7510522..74ed988 100644
--- a/.classpath
+++ b/.classpath
@@ -1,14 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry excluding="**" kind="src" output="target/test-classes" path="src/test/resources">
+	<classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources">
 		<attributes>
-			<attribute name="test" value="true"/>
 			<attribute name="maven.pomderived" value="true"/>
 			<attribute name="optional" value="true"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources">
+	<classpathentry excluding="**" kind="src" output="target/test-classes" path="src/test/resources">
 		<attributes>
+			<attribute name="test" value="true"/>
 			<attribute name="maven.pomderived" value="true"/>
 			<attribute name="optional" value="true"/>
 		</attributes>
diff --git a/pom.xml b/pom.xml
index bb959ca..bd5b546 100644
--- a/pom.xml
+++ b/pom.xml
@@ -45,11 +45,6 @@
 				<type>pom</type>
 				<scope>import</scope>
 			</dependency>
-			<dependency>
-				<groupId>org.aspectj</groupId>
-				<artifactId>aspectjrt</artifactId>
-				<version>1.8.2</version>
-			</dependency>
 		</dependencies>
 		<!-- https://mvnrepository.com/artifact/org.apache.tika/tika-parsers -->
 	</dependencyManagement>
diff --git a/src/main/java/org/gcube/data/access/storagehub/handlers/items/Item2NodeConverter.java b/src/main/java/org/gcube/data/access/storagehub/handlers/items/Item2NodeConverter.java
index b7b798a..18fdacc 100644
--- a/src/main/java/org/gcube/data/access/storagehub/handlers/items/Item2NodeConverter.java
+++ b/src/main/java/org/gcube/data/access/storagehub/handlers/items/Item2NodeConverter.java
@@ -92,6 +92,7 @@ public class Item2NodeConverter {
 
 	}
 
+	@SuppressWarnings("unchecked")
 	private void iterateItemNodeAttributeFields(Object object, Node parentNode, String nodeName) throws Exception{
 		
 		AttributeRootNode attributeRootNode = object.getClass().getAnnotation(AttributeRootNode.class);
@@ -268,6 +269,7 @@ public class Item2NodeConverter {
 		node.setProperty(NodeProperty.DESCRIPTION.toString(), description);
 	}
 	
+	@SuppressWarnings("unchecked")
 	public void updateOwnerOnSubTree(Node node, String owner) throws RepositoryException, BackendGenericError {
 		Class<? extends Item> classToHandle = (Class<? extends Item>)ClassHandler.instance().get(node.getPrimaryNodeType().getName());
 		if (classToHandle==null) return;
diff --git a/src/main/java/org/gcube/data/access/storagehub/handlers/items/Node2ItemConverter.java b/src/main/java/org/gcube/data/access/storagehub/handlers/items/Node2ItemConverter.java
index 9cf9b3f..50325fa 100644
--- a/src/main/java/org/gcube/data/access/storagehub/handlers/items/Node2ItemConverter.java
+++ b/src/main/java/org/gcube/data/access/storagehub/handlers/items/Node2ItemConverter.java
@@ -104,7 +104,7 @@ public class Node2ItemConverter {
 	private <T extends Item> T retrieveItem(Node node, List<String> excludes, Class<T> classToHandle) throws RepositoryException, BackendGenericError{
 		T item;
 		try {
-			item = classToHandle.newInstance();
+			item = classToHandle.getDeclaredConstructor().newInstance();
 		}catch (Exception e) {
 			throw new BackendGenericError(e);
 		}
@@ -194,7 +194,7 @@ public class Node2ItemConverter {
 	}
 
 	private <T> T iterateNodeAttributeFields(Class<T> clazz, Node node) throws Exception{
-		T obj = clazz.newInstance();
+		T obj = clazz.getDeclaredConstructor().newInstance();
 		for (Field field : retrieveAllFields(clazz)){
 			if (field.isAnnotationPresent(Attribute.class)){
 				setAttributeFieldCheckingDefault(field, obj, node);
@@ -252,6 +252,7 @@ public class Node2ItemConverter {
 	}
 
 
+	@SuppressWarnings("unchecked")
 	private <T> void setListNode(Field field, T instance, Node node) throws Exception{
 		field.setAccessible(true);
 		String exclude = field.getAnnotation(ListNodes.class).excludeTypeStartWith();
diff --git a/src/main/java/org/gcube/data/access/storagehub/storage/backend/impl/S3Backend.java b/src/main/java/org/gcube/data/access/storagehub/storage/backend/impl/S3Backend.java
index 4e14bd2..477dbbc 100644
--- a/src/main/java/org/gcube/data/access/storagehub/storage/backend/impl/S3Backend.java
+++ b/src/main/java/org/gcube/data/access/storagehub/storage/backend/impl/S3Backend.java
@@ -16,9 +16,10 @@ import org.slf4j.LoggerFactory;
 import com.amazonaws.ClientConfiguration;
 import com.amazonaws.Protocol;
 import com.amazonaws.auth.AWSCredentials;
+import com.amazonaws.auth.AWSStaticCredentialsProvider;
 import com.amazonaws.auth.BasicAWSCredentials;
 import com.amazonaws.services.s3.AmazonS3;
-import com.amazonaws.services.s3.AmazonS3Client;
+import com.amazonaws.services.s3.AmazonS3ClientBuilder;
 import com.amazonaws.services.s3.S3ClientOptions;
 import com.amazonaws.services.s3.model.ObjectMetadata;
 
@@ -31,9 +32,6 @@ public class S3Backend extends StorageBackend{
 	String bucketName;
 	AmazonS3 client;
 
-	//private static final long PART_SIZE = 100000000; 
-
-
 	@Override
 	protected void setPayloadConfiguration(PayloadBackend payloadConfiguration) {
 		super.setPayloadConfiguration(payloadConfiguration);
@@ -56,9 +54,12 @@ public class S3Backend extends StorageBackend{
 			ClientConfiguration clientConfig = new ClientConfiguration();
 			clientConfig.setProtocol(Protocol.HTTPS);			
 			
-			client = new AmazonS3Client(credentials, clientConfig);
+			client = AmazonS3ClientBuilder.standard()
+					.withCredentials(new AWSStaticCredentialsProvider(credentials)).withClientConfiguration(clientConfig).build(); 
+			
+			
 			client.setEndpoint(url);
-			client.setS3ClientOptions(new S3ClientOptions().withPathStyleAccess(true));
+			client.setS3ClientOptions(S3ClientOptions.builder().setPathStyleAccess(true).build());
 			
 			if (createBucket && !client.doesBucketExistV2(bucketName)) { 
 				client.createBucket(bucketName);