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compile time constants and string literals

 
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I would like to know, for COMPILE TIME CONSTANTS, memory is allocated at runtime only right ? But the compiler keeps track of these compile time constant variable's values right ?

 
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I don't understand your question. All memory is allocated at runtime, no?
 
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ya ya it is .

But or example :



line 11 shows an error, but if final keyword is added to this line it compiles. so it is clear that the compile time constants are being considered here at compile time. so thats what i was asking actually.
 
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The error that you are speaking of @shambhavi sham does not have to do with the use final.
When I try to compile the code as is I get the following:


The problem with this code:


is that the compiler cannot say for sure that the variables b, c or d have values. However you are sure that you want to use them not matter what. If you change the code to this:

You get the expected results and there is not a final in sight.

If you do change:

to

then you do not need to initialize because the compiler knows that no matter what a will be greater then 0 and the other variables will get values.

You could also change your code to something like this:

or this:

And you would still get the results that you expected.
I think that the topic to look into here variable initialization.
 
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shambhavi sham wrote:
line 11 shows an error, but if final keyword is added to this line it compiles. so it is clear that the compile time constants are being considered here at compile time. so thats what i was asking actually.



Hate to point this out, but isn't that obvious?

Of course, compile time constants are used at compile time. That's why they are called compile time constants...

Henry
 
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