设计模式
单例模式
饿汉式
public class Hunger { public static void main(String[] args) { ExampleHunger instance = ExampleHunger.getInstance(); System.out.println(instance); } } class ExampleHunger{ private String name; private static ExampleHunger example = new ExampleHunger("张三"); private ExampleHunger(String name) { this.name = name; } public static ExampleHunger getInstance(){ return example; } @Override public String toString() { return "Example{" + "name='" + name + '\'' + '}'; } }
懒汉式
public class Lazy { public static void main(String[] args) { ExampleLazy instance = ExampleLazy.getInstance(); System.out.println(instance); } } class ExampleLazy{ private String name; private static ExampleLazy example; private ExampleLazy(String name) { this.name = name; } public static ExampleLazy getInstance(){ if (example == null){ example = new ExampleLazy("张三"); } return example; } @Override public String toString() { return "ExampleLazy{" + "name='" + name + '\'' + '}'; } }
模板模式