Reasons to prefer Java over Perl:

• You want to use a fancy library which is available in Java, but not in Perl
• Your client pays for Java, but not for Perl, and you need the money
• You want to run your application on many platforms without requiring the user to install Perl (assuming that most people have installed jvm anyway)

Reasons which might make your client wanting you to stick with Perl instead of Java:

• You don't depend on the money and your client doesn't want to loose you as a programmer
• You tell the client that in order to switch to Java, it costs so much more money to recode everything, that he could for the same amount spend three months in a whirlpool in the Emirates Hotel in Dubai