制作一个智能的侦听器通知程序以避免到处重复代码 [英] Making a smart listeners notifier to avoid code duplication everywhere

问题描述

注意:代码是线程安全的，换句话说，是单线程的.只有我可以将自己从听众列表中删除.

ATTENTION: The code is thread-safe, in other words, single-threaded. Only I can remove myself from the list of listeners.

我有 1000 个不同的侦听器 ArrayList，我必须使用如下代码通知它们:

I have 1000 different ArrayLists of listeners that I have to notify with code like below:

protected void onFlushed() {
    int size = listeners.size();
    for (int i = 0; i < size; i++) {
        listeners.get(i).onFlushed();
        int newSize = listeners.size();
        if (newSize == size - 1) {
            size--;
            i--;
        } else if (newSize != size) {
            throw new ConcurrentModificationException("List was altered while iterating! oldSize=" + size + " newSize=" + newSize);
        }
    }
}

有没有一种聪明的方法来创建一个通知程序类，它可以接受任何侦听器的 ArrayList 和任何侦听器方法，并为我执行下面的逻辑，或者我必须为每个侦听器方法在任何地方复制上面的代码?

Is there a smart way to create a Notifier class that can take any ArrayList of listeners plus any listener method and perform the logic below for me OR I have to duplicate the code above everywhere for every listener method?

我对 Java 的要求是否过高?:(

Am I asking too much from Java? :(

推荐答案

在当前的 Java 中，无法像在函数式语言中那样传递方法，但您可以创建一个 Function

域、范围> 接口并传递实现该接口的对象.

In current Java, there is no way to pass a method around, as you might do in a functional language, but you can create a Function<Domain, Range> interface and pass around objects implementing that interface.

您可以考虑使用 Guava，它提供了类似于功能习语和列表的内容-领悟.

You might consider using Guava, which supplies something resembling functional idioms and list-comprehension.

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