带有静态成员的java初始化顺序

Question

I am not sure whether I have a correct model of Java initialization mechanism in my head. Each class follows the following:

1. Initialize superclass, if there exists one
2. Initialize yourself

Initialize follows the following:

1. Initialize static and instance variables which have their values set outside of initializer.
2. Run static initialization block
3. Run constructor block

Is that precise/correct?

Answer 1

According to the Java language specification , your assumptions are more or less correct. The exceptions are that:

1. instance variables are run when the class is constructed (together with the constructor) after the class is initialized,
2. final static variables with compile-time constant expressions are loaded before even attempting to load the superclass, and
3. the static initialization block is run together with the static variables as one block, in the order they appear in the code.

Answer 2

Code execute as below -

Static init blocks run once, when the class is first loaded.

Static Variable

All Super Constructor.

Instance init blocks run after the constructor's call to super().

instance variable.

(Init blocks execute in the order they appear.)