} catch (Exception ex) {
    ex.printStackTrace(new PrintStream(yourOutputStream));
}

catch(Exception e) {
    e.printStacktrace(System.out);
}

StringWriter writer = new StringWriter();
PrintWriter printWriter = new PrintWriter( writer );
exception.printStackTrace( printWriter );
printWriter.flush();

String stackTrace = writer.toString();

out = some stream ...
try
{
}
catch ( Exception cause )
{
      cause . printStrackTrace ( new PrintStream ( out ) ) ;
}