src/main/java/com/alipay/remoting/Connection.java
public void onClose() {
        Iterator<Entry<Integer, InvokeFuture>> iter = invokeFutureMap.entrySet().iterator();
        while (iter.hasNext()) {
            Entry<Integer, InvokeFuture> entry = iter.next();
            iter.remove();
            InvokeFuture future = entry.getValue();
            if (future != null) {
                future.putResponse(future.createConnectionClosedResponse(this.getRemoteAddress()));
                future.cancelTimeout();
                future.tryAsyncExecuteInvokeCallbackAbnormally();
            }
        }
    }
public void onClose() {
        Iterator<Entry<Integer, InvokeFuture>> iter = invokeFutureMap.entrySet().iterator();
        while (iter.hasNext()) {
            Entry<Integer, InvokeFuture> entry = iter.next();
            iter.remove();
            InvokeFuture future = entry.getValue();
            if (future != null) {
                future.putResponse(future.createConnectionClosedResponse(this.getRemoteAddress()));
                future.cancelTimeout();
                future.tryAsyncExecuteInvokeCallbackAbnormally();
            }
        }
    }
Do something when closing.