code: void emitContent(Location from, Location until, SourceHandler handler)
              throws SAXException {
          if (from.compareTo(until) >= 0) {
              return;
          }
          int fromLine = from.getLine();
          int untilLine = until.getLine();
          Line line = getLine(fromLine);
          if (fromLine == untilLine) {
              try {
                  handler.characters(line.getBuffer(),
                          line.getOffset() + from.getColumn(),
                          until.getColumn() - from.getColumn());
              } catch (ArrayIndexOutOfBoundsException e) {
              }
          } else {
              // first line
              int length = line.getBufferLength() - from.getColumn();
              if (length > 0) {
                  if (!((fromLine == 0 || fromLine == lines.size() - 1)
                          && this.isCss)) {
                      handler.characters(line.getBuffer(),
                              line.getOffset() + from.getColumn(), length);
                  }
              }
              if (fromLine + 1 != lines.size()) {
                  if (!(fromLine == 0 && this.isCss)) {
                      handler.newLine();
                  }
              }
              // lines in between
              int wholeLine = fromLine + 1;
              while (wholeLine < untilLine) {
                  line = getLine(wholeLine);
                  handler.characters(line.getBuffer(), line.getOffset(),
                          line.getBufferLength());
                  wholeLine++;
                  if (wholeLine != lines.size()) {
                      handler.newLine();
                  }
              }
              // last line
              int untilCol = until.getColumn();
              if (untilCol > 0) {
                  line = getLine(untilLine);
                  if (!(untilLine == lines.size() - 1 && this.isCss)) {
                      handler.characters(line.getBuffer(), line.getOffset(),
                              untilCol);
                  }
              }
          }
      }
docs: Emits content between from a location (inclusive) until a location
  (exclusive).
  
  @param from
  @param until
  @param handler
  @throws SAXException