transport/server/play-server/src/main/java/play/server/Server.java
public static Server forRouter(Mode mode, int port, Function<BuiltInComponents, Router> block) {
    return new Builder().mode(mode).http(port).build(block);
  }
public static Server forRouter(Mode mode, int port, Function<BuiltInComponents, Router> block) {
    return new Builder().mode(mode).http(port).build(block);
  }
Create a server for the router returned by the given block.

@param block The block which creates a router.
@param mode The mode the server will run on.
@param port The port the server will run on.
@return The running server.