code: private String extractContent(MustacheTagType tagType, String buffer) {
  
          switch (tagType) {
          case VARIABLE:
              return buffer.trim();
          case UNESCAPE_VARIABLE:
              return (buffer.charAt(0) == ((String) EngineConfigurationKey.START_DELIMITER
                      .getDefaultValue()).charAt(0) ? buffer.substring(1,
                      buffer.length() - 1).trim() : buffer.substring(1).trim());
          case SECTION:
          case INVERTED_SECTION:
          case PARTIAL:
          case EXTEND:
          case EXTEND_SECTION:
          case SECTION_END:
          case NESTED_TEMPLATE:
          case COMMENT:
              return buffer.substring(1).trim();
          case DELIMITER:
              return buffer.trim();
          default:
              return null;
          }
      }
docs: Extract the tag content.
  
  @param buffer
  @return