question: private void emitListAdd ( Method method , String fieldName , StringBuilder builder ) { builder . append ( "    public void " ) ; builder . append ( getListAdderName ( fieldName ) ) ; builder . append ( "(" ) ; builder . append ( getTypeArgumentImplName ( ( ParameterizedType ) method . getGenericReturnType ( ) , 0 ) ) ; builder . append ( " v) {\n      " ) ; builder . append ( getEnsureName ( fieldName ) ) ; builder . append ( "();\n      " ) ; builder . append ( fieldName ) ; builder . append ( ".add(v);\n" ) ; builder . append ( "    }\n\n" ) ; }
target:  Emits an add method to add to a list. If the list is null, it is created.