Static Initialization Blocks in Java

Static Initialization Block:

In Java, a static initialization block is a piece of code within a class that gets executed only once when the class is loaded into memory by the Java Virtual Machine (JVM). The primary goal of a static initialization block is to initialize static fields or perform any necessary one-time setup tasks for the class.

⚫ Static block executes automatically.

static-initialization-blocks project:

MyClass.java 

public class MyClass {

    // Static variable
    static String message;

    // Static initialization block
    static {
        message = "Hello world!";
    }
}

Main.java 

public class Main {
    public static void main(String[] args) {
        MyClass myClass = new MyClass();
        System.out.println(myClass.message);
        // Output: Hello world!
    }
}

static-initialization-blocks-with-constructor project:

MyClass.java 

public class MyClass {

    // Static variable
    static String message;

    // Static initialization block
    static {
        message = "Hello world!";
    }

    // Constructor
    public MyClass() {
        message = "Hello from constructor!";
    }
}

Main.java 

/**
 * Order:
 * <p> 1. fields
 * <p> 2. static block
 * <p> 3. constructor
 */
public class Main {
    public static void main(String[] args) {
        MyClass myClass = new MyClass();
        System.out.println(myClass.message);
        // Output: Hello from constructor!
    }
}

💫The End 💫