用另一个最终静态变量初始化最终静态变量时的内存消耗

Question

My question is, if I creates a final static variable in a class and initialize it with another final static variable (already declared and initialized). What would be the memory consumption for both the variables.

For example:-

class SomeClass{

private static final byte VARIABLE_1 = 0x01;

private static final byte VARIABLE_2 = VARIABLE_1;

...

}

What would be the memory consumed by VARIABLE_1, VARIABLE_2 ?

Thanks in advance.

Answer 1

In your example, and at runtime, 0 bytes. final static primitives are in-lined by the compiler they are constants.

Answer 2

class files contain a copy of the constant value of any static final fields it uses.so memory it is using is negligible.

Class SomeClass declares two constants, VARIABLE_1 and VARIABLE_2 , and initializes them with expressions that are compile-time constants.

The compiler knows that VARIABLE_1 represents the value 0x01 and VARIABLE_2 represents the value 0x01 . When the SomeClass class is loaded by a Java Virtual Machine, VARIABLE_1 and VARIABLE_2 are not stored as class variables in the method area.

The VARIABLE_1 and VARIABLE_2 fields are not class variables, they are constants, the Java compiler places the constant int values they represent into the constant pool of any class that uses them.