protected static <T> T parseEDIMessage(Class<T> clz, Reader reader)
      throws EDIMessageException, InstantiationException, IllegalAccessException,
          InvocationTargetException, ClassNotFoundException, ConversionException {
    if (!clz.isAnnotationPresent(EDIMessage.class)) {
      throw new EDIMessageException("Not EDI Message Class.");
    }
    EDIMessage ediMessage = clz.getAnnotation(EDIMessage.class);

    SegmentIterator segmentIterator =
        new SegmentIterator(reader, ediMessage.segmentDelimiter(), true);

    Field[] fields = clz.getDeclaredFields();
    Iterator<Field> fieldIterator = Arrays.asList(fields).iterator();

    T obj = clz.newInstance();

    Queue<String> lookAhead = new LinkedList<String>();
    while (fieldIterator.hasNext() && (segmentIterator.hasNext() || lookAhead.size() > 0)) {
      parseEDISegmentOrSegmentGroup(ediMessage, obj, fieldIterator, lookAhead, segmentIterator);
    }
    return obj;
  }
  protected static Queue<String> queueLinesForType(
      EDIMessage ediMessage,
      EDISegment segment,
      Queue<String> lookAhead,
      SegmentIterator SegmentIterator) {
    Queue<String> segments = new LinkedList<String>();

    while (SegmentIterator.hasNext()) {
      String line = SegmentIterator.next();
      StringTokenizer tokenizer =
          new StringTokenizer(line, CharUtils.toString(ediMessage.elementDelimiter()));
      String token = tokenizer.nextToken();

      if (StringUtils.equals(segment.tag(), token)) {
        segments.add(line);
      } else {
        lookAhead.add(line);
        break;
      }
    }

    return segments;
  }
  protected static FieldMatch advanceToMatch(
      EDIMessage ediMessage, Iterator<Field> fieldIterator, String line) {
    // advance the reader, read the line.
    StringTokenizer tokenizer =
        new StringTokenizer(line, CharUtils.toString(ediMessage.elementDelimiter()));

    // first token is always the tag.
    String ediSegmentTag = tokenizer.nextToken();

    while (fieldIterator.hasNext()) {
      Field field = fieldIterator.next();
      if (matchesSegment(field, ediSegmentTag)) {
        LOG.debug(
            "SegmentMatch[" + ediSegmentTag + " -> " + field.getType().getName() + "] :: " + line);
        return new FieldMatch(field, line);
      }

      if (LOG.isDebugEnabled()) {
        LOG.debug("Field: " + field + " does not match: " + line);
      }
    }

    return null;
  }
  protected static <T> void parseEDISegmentFields(
      EDIMessage ediMessage, Object segment, String segmentLine)
      throws IllegalAccessException, InvocationTargetException, ClassNotFoundException,
          ConversionException, InstantiationException {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Before Field Values: " + ReflectionToStringBuilder.toString(segment));
      LOG.debug("Segment Values: " + segmentLine);
    }

    // now, tokenize the line, and set the fields.
    StrTokenizer tokenizer = new StrTokenizer(segmentLine, ediMessage.elementDelimiter());

    tokenizer.setEmptyTokenAsNull(true);
    tokenizer.setIgnoreEmptyTokens(false);

    // move past the initial tag.
    tokenizer.next();

    Iterator<Field> fieldIterator =
        Arrays.asList(segment.getClass().getDeclaredFields()).iterator();
    while (tokenizer.hasNext() && fieldIterator.hasNext()) {
      Field field = fieldIterator.next();
      String val = tokenizer.nextToken();

      // check field to see if it is a component of regular field type.
      if (field.isAnnotationPresent(EDIComponent.class)) {
        EDIComponent ediComponent = field.getAnnotation(EDIComponent.class);
        Collection obj = CollectionFactory.newInstance(field.getType());
        Class objType = getCollectionType(field);

        char componentDelimiter =
            ediComponent.delimiter() == Character.UNASSIGNED
                ? ediMessage.componentDelimiter()
                : ediComponent.delimiter();

        // parse each element to the collection.
        StrTokenizer componentTokenizer = new StrTokenizer(val, componentDelimiter);
        componentTokenizer.setEmptyTokenAsNull(true);
        componentTokenizer.setIgnoreEmptyTokens(false);

        while (componentTokenizer.hasNext()) {
          String component = componentTokenizer.nextToken();
          Object fieldObj =
              objType.cast(FieldAwareConverter.convertFromString(objType, field, component));
          obj.add(fieldObj);
        }
        BeanUtils.setProperty(segment, field.getName(), obj);
      } else {
        if (val == null) {
          LOG.debug("  " + field.getName() + " -> null");
          continue;
        }

        // try and populate the field.

        try {
          Object fieldObj = FieldAwareConverter.convertFromString(field.getType(), field, val);
          LOG.debug("  " + field.getName() + " -> " + val);

          BeanUtils.setProperty(segment, field.getName(), fieldObj);
        } catch (Exception e) {
          throw new ConversionException(
              "Exception setting: "
                  + segment.getClass()
                  + "."
                  + field.getName()
                  + " with value: "
                  + val,
              e);
        }
      }
    }

    if (LOG.isDebugEnabled()) {
      LOG.debug("After Field Values: " + ReflectionToStringBuilder.toString(segment));
    }
  }
  protected static <T> void processSegmentGroup(
      EDIMessage ediMessage,
      T object,
      Queue<String> lookAhead,
      SegmentIterator segmentIterator,
      FieldMatch fm)
      throws InstantiationException, IllegalAccessException, InvocationTargetException,
          ClassNotFoundException, ConversionException, EDIMessageException {

    LOG.debug("Object: " + ReflectionToStringBuilder.toString(object));
    LOG.debug("Field: " + fm.getField().getName());

    Class<?> segmentGroupClass = getEDISegmentOrGroupType(fm.getField());
    if (!segmentGroupClass.isAnnotationPresent(EDISegmentGroup.class)) {
      throw new EDIMessageException("Segment Group should have annotation.");
    }

    LOG.debug("Segment Group Type: " + segmentGroupClass);

    String line = fm.getLine();
    EDISegmentGroup es = segmentGroupClass.getAnnotation(EDISegmentGroup.class);

    if (StringUtils.equals(es.header(), line)) {
      // feed line.
    } else {
      LOG.debug("Adding to Look Ahead: " + line);
      lookAhead.add(line);
    }

    if (Collection.class.isAssignableFrom(fm.getField().getType())) {
      Collection obj = CollectionFactory.newInstance(fm.getField().getType());
      BeanUtils.setProperty(object, fm.getField().getName(), obj);

      String segmentTag = getSegmentTag(fm.getField(), true);

      while (true) {
        LOG.debug("Looping to collect Collection of Segment Groups");
        // parse the group...
        Field[] fields = segmentGroupClass.getDeclaredFields();
        final List<Field> fieldsList = Arrays.asList(fields);
        ListIterator<Field> fieldIterator = fieldsList.listIterator(0);

        Object collectionObj = segmentGroupClass.newInstance();
        while (fieldIterator.hasNext() && (segmentIterator.hasNext() || lookAhead.size() > 0)) {
          if (startOfNewRecursiveObject(fieldIterator, fieldsList, segmentGroupClass)) {
            String next = lookAhead.size() > 0 ? lookAhead.remove() : segmentIterator.next();
            lookAhead.add(next);
            if (!isSegmentHeirarchicalLevelAndDeeperLevel(
                line, next, Character.toString(ediMessage.elementDelimiter()))) {
              LOG.debug("Reaching new instance of list.");
              break;
            }
          }
          parseEDISegmentOrSegmentGroup(
              ediMessage, collectionObj, fieldIterator, lookAhead, segmentIterator);
        }

        obj.add(collectionObj);

        // look to next line...
        String nextLine = lookAhead.size() > 0 ? lookAhead.remove() : segmentIterator.next();
        // get the first element of the line.
        StrTokenizer nextLineTokenizer = new StrTokenizer(nextLine, ediMessage.elementDelimiter());

        if (StringUtils.equals(segmentTag, nextLineTokenizer.nextToken())) {
          if (!isSegmentEqual(line, nextLine, Character.toString(ediMessage.elementDelimiter()))) {
            LOG.debug("Reaching new collection");
            lookAhead.add(nextLine);
            break;
          }
          LOG.debug("Might be a repeat..");
          LOG.debug("Next line: " + line);
          lookAhead.add(nextLine);
        } else {
          lookAhead.add(nextLine);
          break;
        }

        // now, look ahead to see whether the next line is of the same
        // object type..
        if (!segmentIterator.hasNext() && lookAhead.size() == 0) {
          break;
        }
      }

    } else {
      Field[] fields = segmentGroupClass.getDeclaredFields();
      Iterator<Field> fieldIterator = Arrays.asList(fields).iterator();

      Object obj = segmentGroupClass.newInstance();
      while (fieldIterator.hasNext() && (segmentIterator.hasNext() || lookAhead.size() > 0)) {
        parseEDISegmentOrSegmentGroup(ediMessage, obj, fieldIterator, lookAhead, segmentIterator);
      }

      BeanUtils.setProperty(object, fm.getField().getName(), obj);
    }

    // look at next...
    if (StringUtils.isNotBlank(es.header())) {
      line = lookAhead.size() > 0 ? lookAhead.remove() : segmentIterator.next();

      if (StringUtils.endsWith(es.footer(), line)) {
        // feed line.
        LOG.debug("Popping footer off of the line iterator.");
      } else {
        lookAhead.add(line);
      }
    }
  }