jooby/src/main/java/org/jooby/Request.java
/**
   * Set a flash attribute. Flash scope attributes are accessible from template engines, by
   * prefixing attributes with <code>flash.</code>. For example a call to
   * <code>flash("success", "OK")</code> is accessible from template engines using
   * <code>flash.success</code>
   *
   * @param name Attribute's name.
   * @param value Attribute's value.
   * @return This request.
   */
Set a flash attribute. Flash scope attributes are accessible from template engines, by
prefixing attributes with flash.. For example a call to
flash("success", "OK") is accessible from template engines using
flash.success

@param name Attribute's name.
@param value Attribute's value.
@return This request.
Set a flash attribute . Flash scope attributes are accessible from template engines by prefixing attributes with flash .. For example a call to flash ( " success " " OK " ) is accessible from template engines using flash . success @param name Attribute ' s name . @param value Attribute ' s value . @return This request .
@Nonnull
  default Request flash(final String name, final Object value) {
    requireNonNull(name, "Attribute's name is required.");
    Map<String, String> flash = flash();
    if (value == null) {
      flash.remove(name);
    } else {
      flash.put(name, value.toString());
    }
    return this;
  }
@ Nonnull default Request flash ( final String name , final Object value ) { requireNonNull ( name , "Attribute's name is required." ) ; Map < String , String > flash = flash ( ) ; if ( value == null ) { flash . remove ( name ) ; } else { flash . put ( name , value . toString ( ) ) ; } return this ; }
Set a flash attribute.
Set a flash attribute .