Consider this case:
public Class1 {
public static final String ONE = "ABC";
public static final String TWO = "DEF";
}
public Class2 {
public void someMethod() {
...
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I have a class declaring constants for my app
public class GroupConstants {
..
public static final int INTEGER_VALUE = 1;
public static ...
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Possible Duplicate:
Is 1/0 a legal Java expression?
Why does this code compile?
class Compiles {
public final static int A = 7/0;
...
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why case constant must be compile time constant in switch?
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I'm returning to Java dev after many years away from it. Is there anyway to get this code to compile?
class Mpeg4
{
public static final ...
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Here is some info I found that should be helpful. A compile-time constant is a value that can be (and is) computed at compile-time. A runtime constant is a value that is computed only while the program is running. If you run the same program more than once: A compile-time constant will have the same value each time the application is ... |
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It means that since the value is known to be constant (and thus unchangeable) at compile time, the compiler is free to insert its value wherever it is referenced. This means that, whenever you change the value, you need to forcibly recompile all classes that reference it, because the compiler will not pick up on that. A runtime constant, on the ... |
hi, Is there a difference between a constant and a compile time constant in Java(correct me if i am wrong). What makes me think like this is this code. final int i = 90; byte b = i ; compiles ane runs fine. where as final int i; i = 90 ; byte b = i ; doesn't compile only. Your ... |
In a switch statement such as the following: final CONSTANT = 10; int x = 2; int y = 3; int z = x + y; switch (x) { case CONSTANT: System.out.println("A"); break; case CONSTANT + 10: System.out.println("B"); break; } z is a variable, and you can switch on it. CONSTANT is a constant, so you can case on it. CONSTANT ... |
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Can anyone tell me what is compile time constant. if i declare a final variable like this final int i=5; This is a compile time constant and if i declare like this final int i; i=5; this is not a compile time constant I want to understand what is a difference between above two intialization of final variables. |
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4.12.4 final Variables A variable can be declared final. A final variable may only be assigned to once. It is a compile time error if a final variable is assigned to unless it is definitely unassigned (16) immediately prior to the assignment. [BLAH BLAH BLAH] We call a variable, of primitive type or type String, that is final and initialized with ... |
Firstly, I'd like to thank Henry Wong for his piece on this subject ( see the forum FAQ if you haven't seen it ). I still have a few issues with this subject though. I should explain that there seems to be some incorrect or out of date info on Java constants on the web, which increases the confusion level. So ... |
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Hi, I am aware that if you are assigning int to a byte without any implicit cast, then the int should be a compile time constant and value should be in byte range. i.e. the below code compile fines. final int b = 10; byte a = b; // compiles fine But if I try the same thing with long, it ... |
It may be easy for a human being to spot that the last two code examples are identical, but it's not so easy for a compiler. You could make its analysis of which code will definitely be executed (or which won't) as complex as you want, and it will still miss opportunities for proving that some code can't be reached. It ... |
A compile-time constant expression is an expression denoting a value of primitive type or a String that does not complete abruptly and is composed using only the following: * Literals of primitive type and literals of type String (3.10.5) * Casts to primitive types and casts to type String * The unary operators +, -, ~, and ! (but not ++ ... |
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Hi to all. I got a problem in understanding compile time constants. I was reading about switch statement, and found a fact: the case constant in switch statement should be compile time constant. and example they have given is: final int a=1; final int b; b=2; int x=0; switch(x) { case a: //ok. case b: //compiler error. } so is it ... |