Pattern to suppress unchecked warnings at the line level

Question

Hi,
As we migrate our APIs to Java 5 (exploiting generics in particular), we are hitting some cases in which we chose not to address the unchecked warnings. To make the code cleaner we thought about annotating methods with @SuppressWarnings("unchecked") but this has the major drawback of turning off all warnings (instead of just the very few we are comfortable leaving behind).
A colleague of mine had a really interesting idea to solve this problem. It can be expressed by the class below:
public final class Cast
  @SuppressWarnings("unchecked")
  public static <T> T uncheckedCast(Object object)
    return (T)object;
}Now we are using this to suppress the specific unchecked warnings we want to ignore. If we decide to revisit these cases, we can just query the usages of the method above.
Although this approach seems really clean to me, I would love to hear your option on it. Can you see any major problem that we are getting ourselves into?
Thanks in advance,
Marcelo

Answer 1

I'm not sure why, but you cannot apply annotation to arbitrary lines. The lowest level of granularity is an assignment statement.
The good news is that the @SuppressWarnings annotation can be applied at that level.
So, whilst this won't work:
  @SuppressWarnings("unchecked")
  someMethodCall((T)obj);this, will:
  @SuppressWarnings("unchecked")
  T tObj = (T)obj;
  someMethodCall(tObj);