package com.atlassian.sal.api.user;
   
   import javax.annotation.Nullable;
   import javax.xml.bind.annotation.adapters.XmlAdapter;
   
   import static org.apache.commons.lang.StringUtils.isNotBlank;
   
   /**
    * A JAXB {@link XmlAdapter} which converts to and from {@link UserKey} objects.
   *
   * @since 2.10.4
   */
  public class UserKeyXmlAdapter extends XmlAdapter<String, UserKey> {
      @Override
      @Nullable
      public UserKey unmarshal(String stringValue) {
          if (isNotBlank(stringValue)) {
              return new UserKey(stringValue);
          } else {
              return null;
          }
      }
  
      @Override
      @Nullable
      public String marshal(UserKey userKey) {
          if (userKey != null) {
              return userKey.getStringValue();
          } else {
              return null;
          }
      }
  }