public class quan {

     String name;

     String says;

     public void setName(String name){

         this.name =name;

     }

     public String getName() {

         return name;

     }

     public String getSays() {

         return says;

     }

     public void setSays(String says) {

         this.says = says;

     }

 }

public class Dog {

    public static void main(String[] args) {

        quan spot = new quan();

        quan scruffy = new quan();

        quan xiaoQ = new quan();

        spot.setName("spot");

        scruffy.setName("scruffy");

        xiaoQ.setName("spot");

        spot.setSays("Ruff!");

        scruffy.setSays("Wuff!");

        xiaoQ.setSays("Ruff!");

        System.out.println(spot.getName());

        System.out.println(spot.getSays());

        System.out.println(scruffy.getName());

        System.out.println(scruffy.getSays());

        System.out.println(xiaoQ.getName());

        System.out.println(xiaoQ.getSays());

        //引用不相等之前

        System.out.println("spot.equals(xiaoQ):" + spot.equals(xiaoQ));

        System.out.print("spot == xiaoQ:");

        System.out.println(spot == xiaoQ);

        xiaoQ = spot;

        //将spot引用赋值给xiaoQ

        System.out.println("spot.equals(xiaoQ):" + spot.equals(xiaoQ));

        System.out.print("spot == xiaoQ:");

        System.out.println(spot == xiaoQ);

    }

}