clarified signature;

--- a/src/Pure/General/http_server.scala	Wed Mar 01 17:09:54 2017 +0100
+++ b/src/Pure/General/http_server.scala	Thu Mar 02 12:09:50 2017 +0100
@@ -13,19 +13,32 @@
 
 object HTTP_Server
 {
-  def apply(handler: HttpExchange => Unit): HTTP_Server =
+  class Handler private[HTTP_Server](val path: String, val handler: HttpHandler)
+  {
+    override def toString: String = path
+  }
+
+  def handler(path: String)(body: HttpExchange => Unit): Handler =
+    new Handler(path, new HttpHandler { def handle(x: HttpExchange) { body(x) } })
+
+  def apply(handlers: Handler*): HTTP_Server =
   {
     val localhost = InetAddress.getByName("127.0.0.1")
 
     val server = HttpServer.create(new InetSocketAddress(localhost, 0), 0)
-    server.createContext("/", new HttpHandler { def handle(x: HttpExchange) { handler(x) } })
     server.setExecutor(null)
-    new HTTP_Server(server)
+
+    val http_server = new HTTP_Server(server)
+    for (handler <- handlers) http_server += handler
+    http_server
   }
 }
 
 class HTTP_Server private(val server: HttpServer)
 {
+  def += (handler: HTTP_Server.Handler) { server.createContext(handler.path, handler.handler) }
+  def -= (handler: HTTP_Server.Handler) { server.removeContext(handler.path) }
+
   def start: Unit = server.start
   def stop: Unit = server.stop(0)