設計模式-單例模式code

package singeton;


import java.security.SecureRandom;

/**
 * @author Zero
 * @since 2019-08-13.
 * Description:
 */
public class HungrySingleton {
    private static final HungrySingleton singleton = new HungrySingleton();
    private final int ID = new SecureRandom().nextInt();

    private HungrySingleton() {
    }

    public static HungrySingleton getSingleton() {
        return singleton;
    }

    public int doSomething() {
//        System.out.println("I'm HungrySingeton " + ID + "!");
        return ID;
    }
}

package singeton;

import java.security.SecureRandom;

/**
 * @author Zero
 * @since 2019-08-13.
 * Description:
 */
public class LazySingleton {
    private static LazySingleton singeton = null;
    private final int ID = new SecureRandom().nextInt();

    private LazySingleton() {
    }

    public static synchronized LazySingleton getSingleton() {
        if (singeton == null) {
            singeton = new LazySingleton();
        }
        return singeton;
    }

    public int doSomething() {
//        System.out.println("I'm LazySingeton " + ID + "!");
        return ID;
    }

}