spring injection is thread-safe? private, return

amy

Code:
public class Test{
private First first;
private Second second;  
public void setFirst(First first){ this.first = first; }
public First getFirst(){  return first; }
// same approach for second
}
.
If I inject the instance through spring injection, is it thread-safe?
If not, how to make it thread-safe?
I googled and found contradict responses, not able to come to any conclusion.

This class will be used by concurrrent request (ie, multi thread).

Please suggest

-RW