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In Java, variables come in three distinct types: local variables, instance variables, and static variables.

Local Variables:

• Defined within a specific method or code block

• Only accessible within that method/block

• Cease to exist when the method/block completes

Instance Variables:

• Belong to a specific object or instance of a class

• Can be accessed throughout the entire class

• Persist as long as the object exists

Static Variables:

• Belong to the class itself, not any specific object

• Can be accessed without creating an instance of the class

• Shared across all objects of that class

• Often used for constants or class-level data

Static vs Non Static

Now Lets see about Control Flow, there are two types of Control Flow.

1. Static Control Flow

   • Identification of static members from top to bottom.

   • Execution of static variable assignments and static blocks from top to bottom.

   • Execution of main method.

2. Instance Control Flow

   • Identification of instance members from top to bottom.

   • Execution of instance variable assignments and instance blocks from top to bottom.

   • Execution of constructor.

Let's see sample code

public class ControlFlow {
   public static void main(String args[]) {
      A1 a1 = new A1();
      a1.displayA1();
   }
}
class A1 {
   A1() {
      System.out.println("In constructor A1");
   }
   static {
      System.out.println("In static block of A1");
   }
   {
      System.out.println("In initialization block of A1");
   }
   void displayA1() {
      System.out.println("In displayA1 method");
   }
}

Output