在 Camel DSL “to" 中使用 Exchange 属性

I want to set a property on a Camel Exchange and then use this property when saving the file. In my camel dsl I have the following:

.process(processorToSetExhangeProperty)  // sets the property <uid> on the exchange
.to("file:/tmp?fileName=file-" + property("uid") + ".xml")

文件被保存为:

"file-property{uid}.xml" though

我的处理器如下:

@Override
public void process(Exchange exchange) throws Exception {
    UUID uuid = UUID.randomUUID();
    exchange.setProperty("uid", uuid.toString());
    exchange.setOut(exchange.getIn());
}

对可能出现的问题或如何实现这一点有任何想法吗?