fixed bug

src/main/java/org/gcube/social_networking/socialnetworking/model/beans/WorkspaceFileItemBean.java

@@ -26,6 +26,10 @@ public class WorkspaceFileItemBean {
 	@NotNull
 	private WorkspaceFolderBean parent;
 	
+	public WorkspaceFileItemBean() {
+		super();
+	}
+
 	public WorkspaceFileItemBean(String id, String name, String title, String path, WorkspaceFolderBean parent) {
 		super();
 		this.id = id;