code: public PropertySource<?> remove(String name) {
          if (logger.isDebugEnabled()) {
              logger.debug("Removing PropertySource '" + name + "'");
          }
          int index = this.propertySourceList.indexOf(PropertySource.named(name));
          return (index != -1 ? this.propertySourceList.remove(index) : null);
      }
docs: Remove and return the property source with the given name, {@code null} if
  not found.
  
  @param name the name of the property source to find and remove