scala 转换被方法调用的对象
在scalatra启动时，会mount多个servlet ,但是servletContext并没有定义mount方法，那为什么servletContext能调用mount方法呢？
这就是scala隐式转换的魅力。
在看scalatra源码时，看到在trait ServletApiImplicits定义了如下代码：1
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22// 用来调用mount
implicit def enrichServletContext(servletContext: ServletContext): RichServletContext =
RichServletContext(servletContext)
```
在RichServletContext中定义了mount方法：
```java
/**
* Mounts a handler to the servlet context. Must be an HttpServlet or a
* Filter.
*
* @param handler the handler to mount
*
* @param urlPattern the URL pattern to mount. Will be appended with `\/\*` if
* not already, as path-mapping is the most natural fit for Scalatra.
* If you don't want path mapping, use the native Servlet API.
*
* @param name the name of the handler
*/
def mount(handler: Handler, urlPattern: String, name: String): Unit = {
mount(handler, urlPattern, name, 1)
}
看如下代码：
implicit def enrichServletContext(sc: String): RichServletContext =
RichServletContext(sc)
case class RichServletContext(sc:String){
def mount():Unit = {
println(sc)
}
}
val ss = "sssss"
ss.mount
在这篇文章中就提到了转换被方法调用的对象
