fairly large webapp: from Java to Python. experiences?

[Giovanni Bajo]

John M. Gabriele wrote:

>> But once it is
>> there, Python is a good choice for web apps. Java is slow
>
> Slow? They're both dynamic languages, but Java is statically
> typed (with less work to do at runtime). For long-running processes,
> I'd guess that Java bytecode executes faster than Python bytecode.


It's not the raw computing performance that counts in this case. I got this
joke in my mail today:

Python:
print "%10.2f" % x

Java:
java.text.NumberFormat formatter = java.text.NumberFormat.getNumberInstance();
formatter.setMinimumFractionDigits(2);
formatter.setMaximumFractionDigits(2);
String s = formatter.format(x);
for (int i = s.length(); i < 10; i++) System.out.print(' ');
System.out.print(s);

Let alone the time it takes to write this routine, I'm hundered percent sure
that the Python's version is also faster at runtime. Python lets you write
pretty expressive code which is easy to maintain and where the computation cost
is easily at the C level. Also Python code is pretty bare-metal, so that
file.write or socket.write go to the syscall immediately. Try that in Java and
you'll find 30 layers of complex abstractions for doubtful benefits and obvious
slowness.
-- 
Giovanni Bajo