Static Initializers and Finite Constants in Java

Question

Given the following simple code in Java.

final class Demo
{
    public static final long serialVersionUID=1L;

    static
    {
        System.out.println("Static constructor invoked.");
    }
}

public final class Main
{
    public static void main(String... args)
    {
        System.out.println(Demo.serialVersionUID);
    }
}

In this simplest of Java code, it is expected that the constructor staticwill be called when the class is Demoinitialized by the method main()through Demo.serialVersionUID, but not .

If this program started without changes, the output would be only 1(the message caused by the Static constructor, as indicated in the block static, will not be displayed).

---

If we want the message to be printed as indicated in the initializer static, then we need to change the declaration statement in the class Demo,

public static final long serialVersionUID=1L;

or,

public static long serialVersionUID=1L;

modifier deletion finalor

public static final long serialVersionUID=1L;

changing the primitive type longto the corresponding shell type long.

, ? static ?