java - 相当于 Java 中的 C# Action() 委托(delegate)吗？

Question

C# 引入了委托(delegate)的概念，它表示可以在不知道目标对象的情况下调用的方法。 在 C# API 中我有一个代码:

var onReadyAction = new Action(() => OnServerStateChangedSubject.OnNext(ServerState.Connected));
var onTerminatedAction = new Action(() => OnServerStateChangedSubject.OnNext(ServerState.Disconnected));

其中OnServerStateChangedSubject.OnNext(ServerState.Connected));是发出有关服务器状态信号的操作。 问题:我如何在java中实现这一点？ 方法代码:

protected TradingClientWithQueue //Client class// KeepConnectAlive()
{
    var onReadyAction = new Action(() => OnServerStateChangedSubject.OnNext(ServerState.Connected));
    var onTerminatedAction = new Action(() => OnServerStateChangedSubject.OnNext(ServerState.Disconnected));

    if (Client == null)
    {
        Client = new TradingClientWithQueue();
        //events 
        Client.OnPacketReceived.Subscribe(OnDataPacketReceivedSubject.OnNext);
        ClientSubscribeOnTerminated(onTerminatedAction);

        Client.OnClientException.Subscribe(OnClientExceptionSubject.OnNext);
        Client.OnClientReady.Subscribe(isReady =>
        {
            AuthenticateClient();
            onReadyAction();
        });

        Client.Connect(Host, Port);
    }
    else
    {
        ClientSubscribeOnTerminated(onTerminatedAction);
        Client.Reconnect(Host, Port);
    }

    return Client;
}

Answer 1

委托(delegate)的等价物是函数式接口(interface)。

Action是一个消耗项目并返回 void 的函数。等效功能接口(interface)最明显的例子是 Consumer<T> .