Roger Ball

Hey Jeff
Thanks for the ideas. I changed my test to only do an assignment. No I/O. Here are the tests

String Litteral Test

long currentNano, endNano; currentNano = System.nanoTime(); testString = "Litteral.. String, 1st Time to assign, 10x : "; // 45 chars testString = "Litteral.. String, 2nd Time to assign, 10x : "; testString = "Litteral.. String, 3rd Time to assign, 10x : "; testString = "Litteral.. String, 4th Time to assign, 10x : "; testString = "Litteral.. String, 5th Time to assign, 10x : "; testString = "Litteral.. String, 6th Time to assign, 10x : "; testString = "Litteral.. String, 7th Time to assign, 10x : "; testString = "Litteral.. String, Time 8th to assign, 10x : "; testString = "Litteral.. String, Time 9th to assign, 10x : "; testString = "Litteral.. String, Time... to assign, 10x : "; endNano = System.nanoTime();


final static Sting test

private static final String TIME_TO_ASSIGN_THIS = "STATIC String, Time assign to variable 10x "; // 45 chars long currentNano, endNano; currentNano = System.nanoTime(); testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; testString = TIME_TO_ASSIGN_THIS; endNano = System.nanoTime();

I ran both tests in a loop 100 times to get an average, still the assignment of a String literal was faster than the assignment of a final static String in between 60 to 70 % of the cases. Now, granted the actual assignment times are very low, in most cases between 100 and 300 nanoseconds. So for most applications this would not be a measurable factor but for an application that must execute a less than 1 millisecond it could be a factor.

Recently I was wondering what the performance difference really is between using a String literal and using a final static String in a Java application. I have always heard that using final static String is significantly faster. So I wrote a small program that would measure the time to print a String literal and the time to print a final static String. Here are some of the conditions I used:
- Both strings are the same length (arbitrary 39 characters) but different strings for each.
- I used System.out.println() for each case
- I ran an arbitrary 100 iterations of doing the same println for each in hopes of eliminating any initialization latency.
- Java 1.6 is used
- I used "System.nanoTime()" to get the timings in each case.

To my surprise the String literal printed faster than the final static String in the tests 60 to 70% of the time. In some cases the String literal printed dramatically faster. Now we are talking about timings in the range of between 15000 nanoseconds to 35000 nanoseconds in each test. However if the application must execute some components at less than one millisecond for instance, this could be influential.

I'd like to know if others have ever run this test and what their findings are.

I am also looking the tests over to see if there are any "gotchas" I might of missed.

Thanks everyone

Does anyone know of an app or open source code that would enable me to validate ejb-local-ref 's prior to deployment?

Question:

Does someone know how one would secure a self-registration emai so that
no one but the email recipient could use the confirmation link. Assume
a scenario such as:

1 A User registers at a site and enters their email.
2 The website creates an account for the user and sends them a
confirmation email with an https link back to the website to confirm
the registration.
3 The user recieves the email, clicks on the link and the user is taken
to a web page where they finish registration.

How is the email link secured so that someone else cannot intercept the
email and register under the user's account an essentially steal there
identity.

Originally posted by Billy Tsai:
what are some good books that specifically covers part 1 exam?
what are the other resources available for SCEA?

There are 2 books one by Cade and one by Paul Allen. You will probably need other resources but these are starting places. Cade book is more accurate but Allen book gives more certification detail objectives and more detail in some areas. There are subjects Allen covers that do not have anything to do with the exam so follow sun's certification guidelines

Originally posted by meg matthews:
Has anyone found and article or resource to aid with studying for the Legacy Connectivity part of the Exam?

Try sun's site and search on topics like screen scrapers, object mapping, JNI, ODBC, COM, etc. Also book by Paul Allen is helpful but not great in this area