What is Static, How to set value of static variable

In Java, the static keyword is used to indicate that a member belongs to the class itself, rather than to instances of the class. This means:

• A static variable is shared across all instances of the class.
• A static method can be called without creating an object.
• A static block runs once when the class is loaded.
• A static class (nested) can be used without an instance of the outer class.

🔹 What Is a Static Variable?

A static variable is also known as a class variable. It is initialized only once, at the time of class loading, and shared among all objects of that class.

✅ Example:

public class Student {
    static String college = "ABC University"; // static variable
    String name;

    Student(String name) {
        this.name = name;
    }

    void display() {
        System.out.println(name + " studies at " + college);
    }

    public static void main(String[] args) {
        Student s1 = new Student("Alice");
        Student s2 = new Student("Bob");

        s1.display(); // Alice studies at ABC University
        s2.display(); // Bob studies at ABC University

        // Changing static variable
        Student.college = "XYZ Institute";

        s1.display(); // Alice studies at XYZ Institute
        s2.display(); // Bob studies at XYZ Institute
    }
}

🛠️ How to Set a Static Variable

You can set a static variable in three ways:

1. At declaration:

static int count = 0;

2. Inside a static block (for complex initialization):

static {
count = 100;
}

3. Using the class name:

Student.college = “New College”;

🧠 Key Points

• Static variables are memory-efficient.
• They are not tied to any object.
• You can access them using the class name directly.