code: public static Set<String> extractDocAnnotation(String anno, JavadocComment jdoc){
          String content = jdoc.getContent().replaceAll("\n[ \t]+\\* ?","\n"); //remove the * at the beginning of a line
          Set<String> result = new LinkedHashSet<>();
  
          while(content.contains(anno)){
              int begin = content.indexOf(anno)+ (anno).length();
              int end = content.indexOf("\n@",begin); //next annotation
  
              if(end > 0){
                  result.add(content.substring(begin,end).trim());
                  content = content.substring(end);
              }else {
                  result.add(content.substring(begin).trim());
                  content = ""; //no more
              }
          }
  
          return result;
      }
docs: <p>
  Extract the content of a doc annotation. The content is always handle as a string.
  The javadoc * and all tabs/space before it are removed as well as the first space after it if present.
  </p>
  
  <p>
  The end of the annotation content is either the end of the content block or the start of an other annotation.
  (i.e it reach a <code>\n@</code> string.
  </p>
  
  @param anno The annotation we are looking for. (must start with @)
  @param jdoc The javadoc block from were the content will be extracted.
  @return the content of the annotation, one entry in the list for each annotation encountered.