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What is the rule with initializing static variables here?

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In the following code which is a question on Enthuware that I'm confused about. Is the static variable i2 never initialized at all or is it okay for an instance initializer to do initialize it?

Answer to below question: The code will compile without error and will print 6 40 0 30 5 when run.


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All static variables are initialized by the JVM to their base values. So the first code block is exactly the same as the second code block:

Now things do get interesting when you add in the final modifier with static variables. final values are considered constants but they are not all treated the same. If you don't initialize a static variable when you declare it then the JVM won't allow you to use it for a switch statement as shown below.

Problem code:

Correct code:

And please don't forget that static or not, any final variable can only be assigned a value once. The assignment can happen when you declare the variable or later on in your code.  
From what I gather,  there are a few oddities with this (e.g. method parameters), however, this is effectively true for the OCA 808 exam.
Heather Keating
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Thank you for your explanation!
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In this topic you'll find a nice overview of the initialization of class, instance and local variables (even when they are marked final). Definitely worth reading!

Hope it helps!
Kind regards,

PS. Always use code tags when posting code to the forums. Unformatted or unindented code is extremely hard to read and many people that might be able to help you will just move along to posts that are easier to read. Please click this link ⇒ UseCodeTags ⇐ for more information. Properly indented and formatted code greatly increases the probability that your question will get quicker, better answers. I already added the code tags for you. See how much easier the code is to read?
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