diff --git a/.settings/org.eclipse.jdt.core.prefs b/.settings/org.eclipse.jdt.core.prefs
index a0e69ab..8b5c4dc 100644
--- a/.settings/org.eclipse.jdt.core.prefs
+++ b/.settings/org.eclipse.jdt.core.prefs
@@ -3,7 +3,7 @@ org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
 org.eclipse.jdt.core.compiler.codegen.methodParameters=do not generate
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
 org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
-org.eclipse.jdt.core.compiler.compliance=1.7
+org.eclipse.jdt.core.compiler.compliance=1.8
 org.eclipse.jdt.core.compiler.debug.lineNumber=generate
 org.eclipse.jdt.core.compiler.debug.localVariable=generate
 org.eclipse.jdt.core.compiler.debug.sourceFile=generate
@@ -13,4 +13,4 @@ org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
 org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=ignore
 org.eclipse.jdt.core.compiler.release=disabled
-org.eclipse.jdt.core.compiler.source=1.7
+org.eclipse.jdt.core.compiler.source=1.8
diff --git a/pom.xml b/pom.xml
index aaa1c16..2621b02 100644
--- a/pom.xml
+++ b/pom.xml
@@ -46,13 +46,6 @@
 				<type>pom</type>
 				<scope>import</scope>
 			</dependency>
-			<dependency>
-				<groupId>com.google.gwt</groupId>
-				<artifactId>gwt</artifactId>
-				<version>${gwtVersion}</version>
-				<type>pom</type>
-				<scope>import</scope>
-			</dependency>
 		</dependencies>
 	</dependencyManagement>
 
@@ -63,6 +56,18 @@
 			<version>${gwtVersion}</version>
 			<scope>provided</scope>
 		</dependency>
+		<dependency>
+			<groupId>com.google.gwt</groupId>
+			<artifactId>gwt-dev</artifactId>
+			<version>${gwtVersion}</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>com.google.gwt</groupId>
+			<artifactId>gwt-servlet</artifactId>
+			<version>${gwtVersion}</version>
+			<scope>provided</scope>
+		</dependency>
 		<dependency>
 			<groupId>com.github.gwtbootstrap</groupId>
 			<artifactId>gwt-bootstrap</artifactId>
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/DatasetBean.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/DatasetBean.java
index bf14fae..4e2d75f 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/DatasetBean.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/DatasetBean.java
@@ -6,12 +6,14 @@ import java.util.Map;
 
 import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata.MetaDataProfileBean;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * This bean will contain during ckan metadata creation information related to the future build.
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
 @SuppressWarnings("serial")
-public class DatasetBean implements Serializable {
+public class DatasetBean implements Serializable, IsSerializable {
 
 	private String id;
 	private String title;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/OrganizationBean.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/OrganizationBean.java
index 197b93b..e1345c8 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/OrganizationBean.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/OrganizationBean.java
@@ -2,11 +2,13 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared;
 
 import java.io.Serializable;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * A ckan organization/group (you can check its nature by looking at getIsOrganization();) like bean with name and title
  * @author Costantino Perciante (costantino.perciante@isti.cnr.it)
  */
-public class OrganizationBean implements Serializable{
+public class OrganizationBean implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = -6566519399945530602L;
 	private String title;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/ResourceElementBean.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/ResourceElementBean.java
index 6c2cb5a..a2c2148 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/ResourceElementBean.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/ResourceElementBean.java
@@ -3,6 +3,7 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared;
 import java.io.Serializable;
 import java.util.List;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
 import com.google.gwt.view.client.ProvidesKey;
 
 
@@ -13,7 +14,7 @@ import com.google.gwt.view.client.ProvidesKey;
  * 
  * @author revisited by Francesco Mangiacrapa
  */
-public class ResourceElementBean implements Comparable<ResourceElementBean>, Serializable{
+public class ResourceElementBean implements Comparable<ResourceElementBean>, Serializable, IsSerializable{
 
 	/** The Constant serialVersionUID. */
 	private static final long serialVersionUID = -1230871392599580669L;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/licenses/LicenseBean.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/licenses/LicenseBean.java
index c3d0580..2b368ed 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/licenses/LicenseBean.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/licenses/LicenseBean.java
@@ -2,11 +2,13 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.licenses;
 
 import java.io.Serializable;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * A license bean like the ckan's one.
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class LicenseBean implements Serializable{
+public class LicenseBean implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = -2079275598877326206L;
 	private String title;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/CategoryWrapper.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/CategoryWrapper.java
index d82cb5e..ad42404 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/CategoryWrapper.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/CategoryWrapper.java
@@ -3,12 +3,14 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata;
 import java.io.Serializable;
 import java.util.List;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * A wrapper for the MetadataCategory class.
  * @see org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataCategory
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class CategoryWrapper implements Serializable{
+public class CategoryWrapper implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = -1949961285656672831L;
 	private String id;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsGroup.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsGroup.java
index 6222b92..311c745 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsGroup.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsGroup.java
@@ -5,12 +5,14 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata;
 
 import java.io.Serializable;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * To be used when a field must be used to create a group.
  * @see org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataGrouping
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class FieldAsGroup implements Serializable{
+public class FieldAsGroup implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = 8096886403417944385L;
 	private boolean create;
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsTag.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsTag.java
index 4f84359..243982b 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsTag.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/FieldAsTag.java
@@ -3,12 +3,14 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata;
 
 import java.io.Serializable;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /** 
  * To be used when a field must be used to create a tag.
  * @see org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataTagging
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class FieldAsTag implements Serializable{
+public class FieldAsTag implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = 5414077853964288094L;
 	public static final String DEFAULT_SEPARATOR = "-";
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetaDataProfileBean.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetaDataProfileBean.java
index 59d1301..bad04db 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetaDataProfileBean.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetaDataProfileBean.java
@@ -3,11 +3,13 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata;
 import java.io.Serializable;
 import java.util.List;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * A MetaDataProfileBean with its children (MetaDataType, MetaDataFields, Categories)
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class MetaDataProfileBean implements Serializable{
+public class MetaDataProfileBean implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = -7377022025375553568L;
 
diff --git a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetadataFieldWrapper.java b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetadataFieldWrapper.java
index afe4cd9..c789a68 100644
--- a/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetadataFieldWrapper.java
+++ b/src/main/java/org/gcube/portlets/widgets/ckandatapublisherwidget/shared/metadata/MetadataFieldWrapper.java
@@ -4,13 +4,15 @@ package org.gcube.portlets.widgets.ckandatapublisherwidget.shared.metadata;
 import java.io.Serializable;
 import java.util.List;
 
+import com.google.gwt.user.client.rpc.IsSerializable;
+
 /**
  * The Class MetadataFieldWrapper.
  * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
  * 
  * @author francesco-mangiacrapa at ISTI-CNR (costantino.perciante@isti.cnr.it)
  */
-public class MetadataFieldWrapper implements Serializable{
+public class MetadataFieldWrapper implements Serializable, IsSerializable{
 
 	private static final long serialVersionUID = -8476731365884466698L;
 	private String fieldName;