--- a/gwt-client/src/main/java/org/dive4elements/river/client/shared/model/MultiAttributeData.java	Thu May 17 13:06:12 2018 +0200
+++ b/gwt-client/src/main/java/org/dive4elements/river/client/shared/model/MultiAttributeData.java	Fri May 18 17:26:26 2018 +0200
@@ -10,10 +10,9 @@
 
 import java.util.Map;
 
+public class MultiAttributeData implements Data {
 
-public class MultiAttributeData
-implements Data
-{
+    private static final long serialVersionUID = 1L;
 
     public static final String TYPE = "multiattribute";
 
@@ -24,24 +23,18 @@
 
     public DataItem[] opts;
 
-
     public MultiAttributeData() {
     }
 
-
-    public MultiAttributeData(
-        String                           label,
-        String                           desc,
-        DataItem[]                       opts,
-        Map<String, Map<String, String>> meta
-    ) {
-        this.label       = label;
+    public MultiAttributeData(final String label, final String desc, final DataItem[] opts, final Map<String, Map<String, String>> meta) {
+        this.label = label;
         this.description = desc;
-        this.opts        = opts;
+        this.opts = opts;
+        this.meta = meta;
     }
 
     public Map<String, Map<String, String>> getMeta() {
-        return meta;
+        return this.meta;
     }
 
     /**
@@ -49,62 +42,63 @@
      *
      * @return the label.
      */
+    @Override
     public String getLabel() {
-        return label;
+        return this.label;
     }
 
-
     /**
      * Returns the description of the item.
      *
      * @return the description.
      */
+    @Override
     public String getDescription() {
-        return description;
+        return this.description;
     }
 
-
     /**
      * Returns the type of the item.
      *
      * @return the type.
      */
+    @Override
     public String getType() {
         return TYPE;
     }
 
-
     /**
      * Returns the data items which represent the allowed options for this Data.
      *
      * @return the allowed options as DataItem array.
      */
+    @Override
     public DataItem[] getItems() {
-        return opts;
+        return this.opts;
     }
 
-
     /**
      * @return always null.
      */
+    @Override
     public DataItem getDefault() {
         return null;
     }
 
-
     /**
      * Returns the values as colon separated string.
      *
      * @return colon separated string.
      */
+    @Override
     public String getStringValue() {
         String data = "";
         boolean first = true;
-        for (int i = 0; i < opts.length; i++) {
+        for (final DataItem opt : this.opts) {
             if (!first) {
                 data += ";";
             }
-            data += opts[i].getStringValue();
+            data += opt.getStringValue();
             first = false;
         }
         return data;