在Java中创建自定义事件

Question

我想用Java做类似的事情，但我不知道怎么做：

当“对象1打招呼”事件发生时， 然后，对象2通过说“你好”来响应该事件

有人能给我一个提示或示例代码吗

Answer 1

有三种不同的设置方法：

1. Thrower在Catcher
2. Catcher在Thrower的内部
3. Thrower和Catcher在本例中的另一个类内Test

THE WORKING GITHUB EXAMPLE I AM CITING默认为选项3，要尝试其他方法，只需取消对要成为main的类的“Optional”代码块的注释，并将该类设置为build.xml文件中的${Main-Class}变量：

抛出代码需要4件事：

import java.util.*;//import of java.util.event

//Declaration of the event's interface type, OR import of the interface,
//OR declared somewhere else in the package
interface ThrowListener {
    public void Catch();
}
/*_____________________________________________________________*/class Thrower {
//list of catchers & corresponding function to add/remove them in the list
    List<ThrowListener> listeners = new ArrayList<ThrowListener>();
    public void addThrowListener(ThrowListener toAdd){ listeners.add(toAdd); }
    //Set of functions that Throw Events.
        public void Throw(){ for (ThrowListener hl : listeners) hl.Catch();
            System.out.println("Something thrown");
        }
////Optional: 2 things to send events to a class that is a member of the current class
. . . go to github link to see this code . . .
}

---

类文件中需要2件东西才能接收来自类的事件

/*_______________________________________________________________*/class Catcher
implements ThrowListener {//implement added to class
//Set of @Override functions that Catch Events
    @Override public void Catch() {
        System.out.println("I caught something!!");
    }
////Optional: 2 things to receive events from a class that is a member of the current class
. . . go to github link to see this code . . .
}