CodeBuilder cb = method.createCodeBuilder();
// TODO don't know if it's safe to pass a null class file.
cb.initialize(null, method);
if ("V".equals(returnType)) { // void
cb.return_();
} else if ("B".equals(returnType) || // byte
"C".equals(returnType) || // char
"I".equals(returnType) || // int
"S".equals(returnType) || // short
"Z".equals(returnType) ) { // boolean