increment - Java Initialize Variable Incremented -

is risky initialize global variable increment of global variable?

example:

int a=0;  int b=a++;  int c=a++;  int d=a++;

this should output:

0,1,2,3

could happen compiler read global value before other?

it behave expected. if try use field before it's defined, compiler throw error:

public class foo {     int = b++; //compiler error here     int b = 0; }

this covered in jls 8.3

for case, output of variables if they're not modified, be:

a = 3 b = 0 c = 1 d = 2

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