fixes

README.md

@@ -2,7 +2,7 @@ spring-xom-marshaller
 ============
 
 [![Maven Central](https://maven-badges.herokuapp.com/maven-central/com.itelg.spring/spring-xom-marshaller/badge.svg)](https://maven-badges.herokuapp.com/maven-central/com.itelg.spring/spring-xom-marshaller)
-[![Codacy Badge](https://api.codacy.com/project/badge/Grade/d134d532488b44e5aaaf1b9775999035)](https://www.codacy.com/app/eggers-julian/spring-xom-marshaller?utm_source=github.com&utm_medium=referral&utm_content=julian-eggers/spring-xom-marshaller&utm_campaign=Badge_Grade)
+[![Codacy Badge](https://api.codacy.com/project/badge/Grade/40fe4c8aa29241429724a9c415051a06)](https://www.codacy.com/app/eggers-julian/spring-xom-marshaller?utm_source=github.com&utm_medium=referral&utm_content=julian-eggers/spring-xom-marshaller&utm_campaign=Badge_Grade)
 [![Coverage Status](https://coveralls.io/repos/julian-eggers/spring-xom-marshaller/badge.svg)](https://coveralls.io/r/julian-eggers/spring-xom-marshaller)
 [![Build Status](https://travis-ci.org/julian-eggers/spring-xom-marshaller.svg?branch=master)](https://travis-ci.org/julian-eggers/spring-xom-marshaller)
 
@@ -23,7 +23,7 @@ Spring XML Marshalling with [XOM](http://www.xom.nu/)
 
 ##### Enable auto-configuration via annotation
 
-[@Autowire](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/annotation/Autowire.html) XomUnmarshaller for further use in [MarshallingHttpMessageConverter](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/http/converter/xml/MarshallingHttpMessageConverter.html) or [MarshallingMessageConverter](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/messaging/converter/MarshallingMessageConverter.html).
+[@Autowire](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/annotation/Autowire.html) XomMarshaller for further use in [MarshallingHttpMessageConverter](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/http/converter/xml/MarshallingHttpMessageConverter.html) or [MarshallingMessageConverter](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/messaging/converter/MarshallingMessageConverter.html).
 
 ```java
 @SpringBootApplication

src/main/java/com/itelg/spring/xom/marshaller/writer/WriterUtil.java

@@ -12,37 +12,37 @@
 
 public class WriterUtil
 {
-    private final DateTimeFormatter format = DateTimeFormatter.ISO_OFFSET_DATE_TIME.withZone(ZoneId.systemDefault());
+    private static final DateTimeFormatter format = DateTimeFormatter.ISO_OFFSET_DATE_TIME.withZone(ZoneId.systemDefault());
 
     private WriterUtil()
     {
 
     }
 
-    public void addAttribute(Element element, String name, Object value)
+    public static void addAttribute(Element element, String name, Object value)
     {
         if (value != null)
         {
             element.addAttribute(new Attribute(name, value.toString()));
         }
     }
 
-    public void addAttribute(Element element, String name, int value)
+    public static void addAttribute(Element element, String name, int value)
     {
         element.addAttribute(new Attribute(name, String.valueOf(value)));
     }
 
-    public void addAttribute(Element element, String name, long value)
+    public static void addAttribute(Element element, String name, long value)
     {
         element.addAttribute(new Attribute(name, String.valueOf(value)));
     }
 
-    public void addAttribute(Element element, String name, double value)
+    public static void addAttribute(Element element, String name, double value)
     {
         element.addAttribute(new Attribute(name, String.valueOf(value)));
     }
 
-    public void addAttribute(Element element, String name, Date value)
+    public static void addAttribute(Element element, String name, Date value)
     {
         if (value != null)
         {
@@ -51,7 +51,7 @@ public void addAttribute(Element element, String name, Date value)
         }
     }
 
-    public void addAttribute(Element element, String name, LocalDateTime value)
+    public static void addAttribute(Element element, String name, LocalDateTime value)
     {
         if (value != null)
         {