01-EventLoopGroup与EventLoop与选择器

// EventLoopGroup的属性有EventLoop集合与chooser选择器
public class NioEventLoopGroup implements EventExecutorGroup {
    private final EventExecutor[] children;

    private static final int DEFAULT_EVENT_LOOP_THREADS = 16;

    private final EventExecutorChooserFactory.EventExecutorChooser chooser;

    ...
}

// 选择器核心方法 executors[idx.getAndIncrement() & executors.length - 1];
private static final class PowerOfTwoEventExecutorChooser implements EventExecutorChooser {
    private final AtomicInteger idx = new AtomicInteger();
    private final EventExecutor[] executors;

    PowerOfTwoEventExecutorChooser(EventExecutor[] executors) {
        this.executors = executors;
    }

    @Override
    public EventExecutor next() {
        return executors[idx.getAndIncrement() & executors.length - 1];
    }
}