Вопрос по ООП (правильно ли реализована задача; Ява)

/**
 * class that can be created only in a single instance  
 * and only by some specific method.
 */
package sinstance;

/**
 * @author A.G
 *
 */
public class SingleInstance {
    private static SingleInstance instance = new SingleInstance();
    private SingleInstance(){
   
    }
    /**
     *
     * @return the pointer to the already existing object
     */
    public static SingleInstance getInstance() {
        return instance;
    }
   
    public void loop() {
        for(int i = 0; i < 10; i++) System.out.println(i);
    }
}

/**
 * Class, that is using to test SingleInstance class
 */
package sinstance;

/**
 * @author A.G
 *
 */
public class FirstTask {

    /**
     * @param args
     */
    public static void main(String[] args) {
        SingleInstance pInst = SingleInstance.getInstance();
        pInst.loop();
    }

}