src/Pure/System/scala.scala
changeset 71849 265bbad3d6af
parent 71673 88dfbc382a3d
child 71850 f640380aaf86
equal deleted inserted replaced
71848:3c7852327787 71849:265bbad3d6af
       
     1 /*  Title:      Pure/System/scala.scala
       
     2     Author:     Makarius
       
     3 
       
     4 Support for Scala at runtime.
       
     5 */
       
     6 
       
     7 package isabelle
       
     8 
       
     9 
       
    10 import java.lang.reflect.{Method, Modifier, InvocationTargetException}
       
    11 
       
    12 import scala.util.matching.Regex
       
    13 
       
    14 
       
    15 object Scala
       
    16 {
       
    17   /** invoke JVM method via Isabelle/Scala **/
       
    18 
       
    19   /* method reflection */
       
    20 
       
    21   private val Ext = new Regex("(.*)\\.([^.]*)")
       
    22   private val STRING = Class.forName("java.lang.String")
       
    23 
       
    24   private def get_method(name: String): String => String =
       
    25     name match {
       
    26       case Ext(class_name, method_name) =>
       
    27         val m =
       
    28           try { Class.forName(class_name).getMethod(method_name, STRING) }
       
    29           catch {
       
    30             case _: ClassNotFoundException | _: NoSuchMethodException =>
       
    31               error("No such method: " + quote(name))
       
    32           }
       
    33         if (!Modifier.isStatic(m.getModifiers)) error("Not at static method: " + m.toString)
       
    34         if (m.getReturnType != STRING) error("Bad method return type: " + m.toString)
       
    35 
       
    36         (arg: String) => {
       
    37           try { m.invoke(null, arg).asInstanceOf[String] }
       
    38           catch {
       
    39             case e: InvocationTargetException if e.getCause != null =>
       
    40               throw e.getCause
       
    41           }
       
    42         }
       
    43       case _ => error("Malformed method name: " + quote(name))
       
    44     }
       
    45 
       
    46 
       
    47   /* method invocation */
       
    48 
       
    49   object Tag extends Enumeration
       
    50   {
       
    51     val NULL, OK, ERROR, FAIL, INTERRUPT = Value
       
    52   }
       
    53 
       
    54   def method(name: String, arg: String): (Tag.Value, String) =
       
    55     Exn.capture { get_method(name) } match {
       
    56       case Exn.Res(f) =>
       
    57         Exn.capture { f(arg) } match {
       
    58           case Exn.Res(null) => (Tag.NULL, "")
       
    59           case Exn.Res(res) => (Tag.OK, res)
       
    60           case Exn.Exn(Exn.Interrupt()) => (Tag.INTERRUPT, "")
       
    61           case Exn.Exn(e) => (Tag.ERROR, Exn.message(e))
       
    62         }
       
    63       case Exn.Exn(e) => (Tag.FAIL, Exn.message(e))
       
    64     }
       
    65 }
       
    66 
       
    67 
       
    68 /* protocol handler */
       
    69 
       
    70 class Scala extends Session.Protocol_Handler
       
    71 {
       
    72   private var session: Session = null
       
    73   private var futures = Map.empty[String, Future[Unit]]
       
    74 
       
    75   override def init(init_session: Session): Unit =
       
    76     synchronized { session = init_session }
       
    77 
       
    78   override def exit(): Unit = synchronized
       
    79   {
       
    80     for ((id, future) <- futures) cancel(id, future)
       
    81     futures = Map.empty
       
    82   }
       
    83 
       
    84   private def fulfill(id: String, tag: Scala.Tag.Value, res: String): Unit =
       
    85     synchronized
       
    86     {
       
    87       if (futures.isDefinedAt(id)) {
       
    88         session.protocol_command("Scala.fulfill", id, tag.id.toString, res)
       
    89         futures -= id
       
    90       }
       
    91     }
       
    92 
       
    93   private def cancel(id: String, future: Future[Unit])
       
    94   {
       
    95     future.cancel
       
    96     fulfill(id, Scala.Tag.INTERRUPT, "")
       
    97   }
       
    98 
       
    99   private def invoke_scala(msg: Prover.Protocol_Output): Boolean = synchronized
       
   100   {
       
   101     msg.properties match {
       
   102       case Markup.Invoke_Scala(name, id) =>
       
   103         futures += (id ->
       
   104           Future.fork {
       
   105             val (tag, result) = Scala.method(name, msg.text)
       
   106             fulfill(id, tag, result)
       
   107           })
       
   108         true
       
   109       case _ => false
       
   110     }
       
   111   }
       
   112 
       
   113   private def cancel_scala(msg: Prover.Protocol_Output): Boolean = synchronized
       
   114   {
       
   115     msg.properties match {
       
   116       case Markup.Cancel_Scala(id) =>
       
   117         futures.get(id) match {
       
   118           case Some(future) => cancel(id, future)
       
   119           case None =>
       
   120         }
       
   121         true
       
   122       case _ => false
       
   123     }
       
   124   }
       
   125 
       
   126   val functions =
       
   127     List(
       
   128       Markup.Invoke_Scala.name -> invoke_scala,
       
   129       Markup.Cancel_Scala.name -> cancel_scala)
       
   130 }