private static String upperCaseFirstChar(String s) {
        if (reservedFieldName(s)) {
            System.err.println("WARNING - field '"+s+"' has a reserved name; using 'My_"+s+"' instead");
            return "My_" + s;
        }
        return s.substring(0, 1).toUpperCase()+s.substring(1);
    }
Returns spaces corresponding to 1 level of indentation
vespa-documentgen-plugin/src/main/java/com/yahoo/vespa/DocumentGenMojo.java