Hi all,

Can anyone please confirm if using a static, pre-created Exception
object in a throw statement across multiple threads, thread-safe? I
have a need to use a pre-created Exception to improve the performance.
I use pre-created exception in production mode, where as new Exception
object in debug mode.

Line 14 in the sample test program below highlights this. Is Line 14,
thread-safe?

    1  public class StaticPreCreatedExceptionTest implements Runnable
{
    2      private static final Exception ex = new Exception("static
pre-created exception");
    3
    4      private String tid = null;
    5
    6      public StaticPreCreatedExceptionTest(String tid) {
    7          this.tid = tid;
    8      }
    9
   10      public void run() {
   11          while ( true ) {
   12              try {
   13                  // is this thread safe?
   14                  throw ex;
   15              }
   16              catch (Exception e) {
   17                  System.out.println(tid + ": caught exception");
   18              }
   19          }
   20      }
   21
   22      public static void main(String args[]) throws Exception {
   23          int MAXTHREADS = 5;
   24
   25          Thread threads[] = new Thread[MAXTHREADS];
   26          for ( int i = 0; i < MAXTHREADS; i++ ) {
   27              threads[i] = new Thread(new
StaticPreCreatedExceptionTest("t" + i));
   28              threads[i].start();
   29          }
   30
   31          for ( int i = 0; i < MAXTHREADS; i++ ) {
   32              // wait until all threads are done
   33              threads[i].join();
   34          }
   35      }
   36  }

I thought it was thread-safe, but current thread stack trace of the
Java core dumps in my software always points to the "throw" statement.
So wanted to confirm from someone.

Thanks,
Shailender