diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/ConditionalEventDefinitionExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/ConditionalEventDefinitionExtension.java
index fa98e6ce..d3062910 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/ConditionalEventDefinitionExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/ConditionalEventDefinitionExtension.java
@@ -24,8 +24,6 @@
 import javax.json.JsonObject;
 import javax.json.JsonObjectBuilder;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.graph.GModelElement;
 import org.openbpmn.bpmn.BPMNTypes;
 import org.openbpmn.bpmn.elements.Event;
@@ -46,8 +44,6 @@
  */
 public class ConditionalEventDefinitionExtension extends AbstractBPMNElementExtension {
 
-    private static Logger logger = LogManager.getLogger(DefaultBPMNSequenceFlowExtension.class);
-
     @Override
     public int getPriority() {
         return 101;
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNEventExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNEventExtension.java
index 2e968a4f..6071c008 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNEventExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNEventExtension.java
@@ -20,8 +20,6 @@
 
 import javax.json.JsonObject;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.graph.GModelElement;
 import org.openbpmn.bpmn.BPMNTypes;
 import org.openbpmn.bpmn.elements.Event;
@@ -32,13 +30,12 @@
 import org.openbpmn.glsp.jsonforms.UISchemaBuilder.Layout;
 
 /**
- * This is the Default BPMNEvent extension providing the JSONForms shemata.
+ * This is the Default BPMNEvent extension providing the JSONForms schemata.
  *
  * @author rsoika
  *
  */
 public class DefaultBPMNEventExtension extends AbstractBPMNElementExtension {
-    private static Logger logger = LogManager.getLogger(DefaultBPMNTaskExtension.class);
 
     public DefaultBPMNEventExtension() {
         super();
@@ -106,5 +103,4 @@ public void updatePropertiesData(final JsonObject json, final BPMNElement bpmnEl
         bpmnElement.setDocumentation(json.getString("documentation"));
 
     }
-
 }
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTaskExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTaskExtension.java
index 25e6e2db..a39ebb1e 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTaskExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTaskExtension.java
@@ -20,8 +20,6 @@
 
 import javax.json.JsonObject;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.graph.GModelElement;
 import org.openbpmn.bpmn.BPMNNS;
 import org.openbpmn.bpmn.BPMNTypes;
@@ -33,15 +31,13 @@
 import org.openbpmn.glsp.jsonforms.UISchemaBuilder.Layout;
 
 /**
- * This is the Default BPMNEvent extension providing the JSONForms shemata.
+ * This is the Default BPMNEvent extension providing the JSONForms schemata.
  *
  * @author rsoika
  *
  */
 public class DefaultBPMNTaskExtension extends AbstractBPMNElementExtension {
 
-    private static Logger logger = LogManager.getLogger(DefaultBPMNTaskExtension.class);
-
     public DefaultBPMNTaskExtension() {
         super();
     }
@@ -105,9 +101,6 @@ public void buildPropertiesForm(final BPMNElement bpmnElement, final DataBuilder
                     addElements("scriptformat"). //
                     addElement("script", "Script", multilineOption); //
         }
-
-        // update corresponding GModelElement....
-
     }
 
     /**
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTextAnnotationExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTextAnnotationExtension.java
index e4736651..8e65643f 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTextAnnotationExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/DefaultBPMNTextAnnotationExtension.java
@@ -21,8 +21,6 @@
 
 import javax.json.JsonObject;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.graph.GModelElement;
 import org.openbpmn.bpmn.BPMNTypes;
 import org.openbpmn.bpmn.elements.TextAnnotation;
@@ -31,10 +29,6 @@
 import org.openbpmn.glsp.jsonforms.SchemaBuilder;
 import org.openbpmn.glsp.jsonforms.UISchemaBuilder;
 import org.openbpmn.glsp.jsonforms.UISchemaBuilder.Layout;
-import org.openbpmn.glsp.model.BPMNGModelFactory;
-import org.openbpmn.glsp.model.BPMNGModelState;
-
-import com.google.inject.Inject;
 
 /**
  * This is the Default TextAnnotation extension providing the JSONForms
@@ -44,10 +38,6 @@
  *
  */
 public class DefaultBPMNTextAnnotationExtension extends AbstractBPMNElementExtension {
-    private static Logger logger = LogManager.getLogger(BPMNGModelFactory.class);
-
-    @Inject
-    protected BPMNGModelState modelState;
 
     public DefaultBPMNTextAnnotationExtension() {
         super();
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/SignalEventDefinitionExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/SignalEventDefinitionExtension.java
index c8c53955..08d6dc1e 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/SignalEventDefinitionExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/SignalEventDefinitionExtension.java
@@ -144,7 +144,7 @@ public void buildPropertiesForm(final BPMNElement bpmnElement, final DataBuilder
     /**
      * This method updates the signalEventDefinitions. The method expects a
      * dataList containing all conditions with its values (including the id).
-     * The method simply overwrites all csignalEventDefinitions.
+     * The method simply overwrites all signalEventDefinitions.
      * 
      * @See addSignalEventDefinitions how we map between the signal name and its id.
      * 
@@ -181,7 +181,7 @@ public void updatePropertiesData(final JsonObject json, final BPMNElement bpmnEl
                     if (signal != null) {
                         eventDefinitionElement.setAttribute("signalRef", signal.getId());
                     } else {
-                        // no signal defintion found - delete signalRef...
+                        // no signal definition found - delete signalRef...
                         eventDefinitionElement.setAttribute("signalRef", "");
                     }
                 } catch (BPMNInvalidReferenceException | BPMNMissingElementException | BPMNInvalidTypeException e) {
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/TimerEventDefinitionExtension.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/TimerEventDefinitionExtension.java
index 702fcc75..35c5a030 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/TimerEventDefinitionExtension.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/extension/TimerEventDefinitionExtension.java
@@ -24,8 +24,6 @@
 import javax.json.JsonObject;
 import javax.json.JsonObjectBuilder;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.graph.GModelElement;
 import org.openbpmn.bpmn.BPMNNS;
 import org.openbpmn.bpmn.BPMNTypes;
@@ -50,8 +48,6 @@
  */
 public class TimerEventDefinitionExtension extends AbstractBPMNElementExtension {
 
-    private static Logger logger = LogManager.getLogger(DefaultBPMNSequenceFlowExtension.class);
-
     @Inject
     protected BPMNGModelState modelState;
 
diff --git a/open-bpmn.glsp-server/src/main/java/org/openbpmn/glsp/jsonforms/DataBuilder.java b/open-bpmn.glsp-server/src/main/java/org/openbpmn/glsp/jsonforms/DataBuilder.java
index 35e7f458..1c1f4fd8 100644
--- a/open-bpmn.glsp-server/src/main/java/org/openbpmn/glsp/jsonforms/DataBuilder.java
+++ b/open-bpmn.glsp-server/src/main/java/org/openbpmn/glsp/jsonforms/DataBuilder.java
@@ -26,7 +26,7 @@
 import javax.json.JsonObjectBuilder;
 
 /**
- * The DataBuilder can be used to define a data structure for JSONFOrms
+ * The DataBuilder can be used to define a data structure for JSONForms
  * <p>
  * The schema of the data is defined by the SchemaBuilder class.
  * <p>