java - 订阅的可抛出 onError 组件未按预期编译

Question

尝试使用 Observable 设置对 RxAndroidBle 连接状态的监控。下面的代码编译（我还不能测试它），但我不完全明白为什么。调用的第二个参数subscribe应该是Action1<java.lang.Throwable> onError. 我是否正确实施了这一点？为什么我不能写

throwable -> throw throwable

当我尝试时，第二个“throwable”被标记为“无法解析符号'throwable'”，并且在“->”和“throw”之间它表示它需要一个右括号、左括号或分号。

// set up monitoring of connection state with a subscription
boolean setConnectionStateNotification() {
    asBleDevice.observeConnectionStateChanges()
        .subscribe(
            connectionState -> asBleConnectionState = connectionState,
            throwable -> new RuntimeException( "Problem with subscription to Connection State Changes: "
                            + throwable.getMessage() )
            );
    return true;
}

TBH 我很难理解 ; 的概念Action1<Throwable>。有人可以解释一下吗？

更新：我想我可能已经弄清楚了。像这样：

 boolean setConnectionStateNotification() {
    asBleDevice.observeConnectionStateChanges() // returns Observable<RxBleConnection.RxBleConnectionState>
        .subscribe(
            connectionState -> asBleConnectionState = connectionState,
            throwable -> { throw new RuntimeException(
                "Problem with subscription to Connection State Changes: "
                    + throwable.getMessage(), throwable );
            },
            ( ) -> RxBleLog.d( "Connection State Observable has completed", null ) // onCompleted() with no arguments
            ); // subscribe
    return true;
}

（我还为 onCompleted() 调用添加了第三个可选处理程序。）

Answer 1

我认为这可能是正确的：

boolean setConnectionStateNotification() {
    asBleDevice.observeConnectionStateChanges() // returns Observable<RxBleConnection.RxBleConnectionState>
        .subscribe(
            connectionState -> asBleConnectionState = connectionState, // save value
            throwable -> { throw new RuntimeException(
                "Problem with subscription to Connection State Changes: "
                    + throwable.getMessage(), throwable );
            },
            ( ) -> RxBleLog.d( "Connection State Observable has completed", null ) // onCompleted() with no arguments
        ); // subscribe
    return true;
}