Java Class

In Java, a class can contain both static and non-static members.

Static Members:

Static members belong to the class rather than individual objects. They are shared across all instances of the class.

Key Points About Static Members:

1. Static Variables:

   • Declared with the static keyword.
   • Memory is allocated only once when the class is loaded, and the same value is accessible by all objects.
   • Example:

    class StaticExample {
        static int counter = 0; // static variable
    }
   

2. Static Methods:

   • Can be called directly using the class name without creating an object.
   • Cannot access non-static variables or methods directly.
   • Example:

    class StaticMethodExample {
        static void display() {
            System.out.println("Static method called");
        }
    }
    StaticMethodExample.display(); // Accessing static method
   

3. Static Blocks:

   • Used for initializing static variables.
   • Executed once when the class is loaded.
   • Example:

    class StaticBlockExample {
        static int num;
        static {
            num = 10; // Static block initializing static variable
        }
    }
   

Non-Static Members:

Non-static members are tied to specific instances of a class. Each object has its own copy.

Key Points About Non-Static Members:

1. Instance Variables:

   • Declared without the static keyword.
   • Each object gets its own separate copy of these variables.
   • Example:

    class NonStaticExample {
        int id; // non-static variable
    }
   

2. Instance Methods:

   • Can access both static and non-static variables.
   • Require an object to be invoked.
   • Example:

    class InstanceMethodExample {
        int id;
        void show() {
            System.out.println("Instance method called: ID is " + id);
        }
    }
    InstanceMethodExample obj = new InstanceMethodExample();
    obj.show(); // Accessing instance method
   

Differences:

Does this give you a clearer understanding? I can go deeper into concepts or practical use cases if you'd like! 😊