calling methods from if statement

i have this code:

public void main() throws InterruptedException, IOException {
    
    boolean a = true;

    if(a == true) {
        methodTwo();
    } else {
        methodOne();
    }    
}

public void methodOne() throws InterruptedException, IOException {
    System.out.println("Using method one!");
}

public void methodTwo() throws InterruptedException, IOException {
    System.out.println("Using method two!");
}

but for some reason when I run the code methodOne() is still being executed after methodTwo() even though a is true

and if a is false methodTwo() is still being executed

the print statement in methodTwo() is executed before the print statement in methodOne() no matter if a is true or false

what i need it to do is if a is true, ONLY execute methodTwo() and vice versa

can anyone help?