Java两大工具库Commons和Guava使用示例详解

/**
 * 支付宝观察者
 *
 * @author 湘王
 */
public class AliPayObserver {
    // 标记当前订阅者是线程安全的，支持并发接收消息
    @AllowConcurrentEvents
    @Subscribe
    public void pay(Account account) {
        if (account.getName().equalsIgnoreCase("ALI")) {
            System.out.println("支付宝 >>>>>> 已付款");
            System.out.println(account.getMessage());
        }
    }
}

/**
 * 微信支付观察者
 *
 * @author 湘王
 */
public class WeixinObserver {
    // 标记当前订阅者是线程安全的，支持并发接收消息
    @AllowConcurrentEvents
    @Subscribe
    public void pay(Account account) {
        if (account.getName().equalsIgnoreCase("WEIXIN")) {
            System.out.println("微信 >>>>>> 已付款");
            System.out.println(account.getMessage());
        }
    }
}

/**
 * 余额支付观察者
 *
 * @author 湘王
 */
public class YuePayObserver {
    // 标记当前订阅者是线程安全的，支持并发接收消息
    @AllowConcurrentEvents
    @Subscribe
    public void pay(Account account) {
        if (account.getName().equalsIgnoreCase("YUE")) {
            System.out.println("余额 >>>>>> 已付款");
            System.out.println(account.getMessage());
        }
    }
}

/**
 * 账户
 *
 * @author 湘王
 */
public class Account {
    private String name;
    private double amount;
    private Date date;
    public Account(String name, double amount, Date date) {
        this.name = name;
        this.amount = amount;
        this.date = date;
    }
    public String getName() {
        return name;
    }
    public String getMessage() {
        StringBuilder sb = new StringBuilder();
        sb.append("账户：").append(this.name).append(", ");
        sb.append("金额：").append(amount).append(", ");
        sb.append("日期：").append(date);
        return sb.toString();
    }
}

/**
 * 事件总线
 *
 * @author 湘王
 */
public class EventBusTest {
    // 回调通知
    public static void notifyObserver() {
        EventBus bus = new EventBus();
        AliPayObserver ali = new AliPayObserver();
        WeixinObserver weixin = new WeixinObserver();
        YuePayObserver yue = new YuePayObserver();
        bus.register(ali);
        bus.register(weixin);
        bus.register(yue);
        Account account1 = new Account("ALI", 1.6, new Date());
        bus.post(account1);
        Account account2 = new Account("WEIXIN", 2.2, new Date());
        bus.post(account2);
        Account account3 = new Account("YUE", 3, new Date());
        bus.post(account3);
    }
    public static void main(String[] args) throws InterruptedException {
        notifyObserver();
    }
}

/**
 * 做家务的接口
 *
 * @author 湘王
 */
public interface HouseWork {
    public void dry();
}

/**
 * 女主人（具体做家务的人）
 *
 * @author 湘王
 */
public class Woman implements HouseWork {
    @Override
    public void dry() {
        System.out.println("可以晾衣服了");
    }
}

/**
 * 洗衣机（Subject类）
 *
 * @author 湘王
 */
public class WashingMachine {
    private Vector<HouseWork> vector = new Vector<>();
    public void register(HouseWork work) {
        vector.add(work);
    }
    public void unregister(HouseWork work) {
        vector.remove(work);
    }
    public void notifyObserver() {
        for (HouseWork work : vector) {
            work.dry();
        }
    }
    public static void main(String[] args) throws InterruptedException {
        // 洗衣机
        WashingMachine machine = new WashingMachine();
        // 女主人
        Woman woman = new Woman();
        // 洗衣机让女主人成为自己的观察者
        machine.register(woman);
        System.out.println("将衣服放到洗衣机。。。");
        System.out.println("买菜、遛娃中。。。");
        Thread.sleep(3000);
        // 通知观察者（女主人），衣服洗完了
        machine.notifyObserver();
    }
}

/**
 * 具体观察者
 *
 * @author 湘王
 */
public class Man {
    @Subscribe
    public void dry(Sheet sheet) {
        System.out.println("可以晾 " + sheet.getName() + " 床单了");
    }
}

/**
 * 事件总线
 *
 * @author 湘王
 */
public class EventBusTest {
    // 回调通知
    public static void notifyObserver() {
        EventBus bus = new EventBus();
        Man man = new Man();
        bus.register(man);
        bus.post(new Sheet("富安娜"));
    }
    public static void main(String[] args) {
        notifyObserver();
    }
}

/**
 * 床单实体类
 *
 * @author 湘王
 */
public class Sheet {
    private String name;
    public Sheet(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}