code: private void checkForFinal(final Expression expression, VariableExpression ve) {
          Variable v = ve.getAccessedVariable();
          boolean isFinal = isFinal(v.getModifiers());
          boolean isParameter = v instanceof Parameter;
          if (isFinal && isParameter) {
              addError("Cannot assign a value to final variable '" + v.getName() + "'", expression);
          }
      }
docs: TODO handle local variables