//Test004.javapublic class Test004 {    public static void main(String[] args) {        int a =8;        int b =8;        if(a==b){            System.out.);        }        else{            System.out.println("a is not equal to b.");        }        /*         * == and equals         *The Operator == works a bit different on objects than on primitives.          When we are using objects and want to check if they are equal, the          operator == wiil say if they are the same, if you want to check if          they are logically equal, you should use the equals method on the object.          For example:        */        String person_a=new String("gavin");        String person_b=new String("gavin");        String person_c=person_a;        System.out.println(person_a==person_b);//這里會輸因為false,        //因為person_a和person_b不是一個對象，分配的物理空間的地址不一樣        System.out.println(person_a.equals(person_b));//這里會輸出true,        //因為person_a和persion_b的邏輯值一樣，都是gavin        System.out.println(person_a==person_c);//這里會輸出true,        //因為person_a和person_b實際上是同一個對象    }}