code: @Override
      public Boolean parameterAsBoolean(String name, boolean defaultValue) {
          // We have to check if the map contains the key, as the retrieval method returns false on missing key.
          if (!request.params().contains(name)) {
              return defaultValue;
          }
          Boolean parameter = parameterAsBoolean(name);
          if (parameter == null) {
              return defaultValue;
          }
          return parameter;
      }
docs: Same like {@link #parameter(String)}, but converts the parameter to
  Boolean if found.
  <p/>
  The parameter is decoded by default.
  
  @param name         The name of the post or query parameter
  @param defaultValue A default value if parameter not found.
  @return The value of the parameter or the defaultValue if not found.