public static void addCustomLevel(Level level, String id) {
        if (level == null) {
            throw new IllegalArgumentException("Parameter level can not be 'null' in this call");
        }
        if (id == null) {
            id = level.getName().substring(0, 1);
        }
        customLevels.put(level, id);
    }
public static void addCustomLevel ( Level level , String id ) { if ( level == null ) { throw new IllegalArgumentException ( "Parameter level can not be 'null' in this call" ) ; } if ( id == null ) { id = level . getName ( ) . substring ( 0 , 1 ) ; } customLevels . put ( level , id ) ; }
Adds level to be treated specially by this formatter.

@param level level to be added to the special list
@param id one character id to use for this level. If it's <code>null</code> first character of the level name will be used