scala.actors: fixed build on JDK 1.4

git-svn-id: http://lampsvn.epfl.ch/svn-repos/scala/scala/trunk@9835 5e8d7ff9-d8ef-0310-90f0-a4852d11357a

build.xml

@@ -134,7 +134,7 @@ INITIALISATION
       <else><fail>System environment could not be determined</fail></else>
     </if>
   <!-- Setting flag for Java versions 1.4.x -->
-    <condition property="java14" else="false">
+    <condition property="java14">
       <contains string="${java.version}" substring="1.4"/>
     </condition>
   <!-- Finding out SVN revision -->
@@ -441,7 +441,7 @@ BUILD QUICK-TEST LAYER
         <pathelement location="${quick.dir}/lib/actors"/>
       </classpath>
       <include name="scala/actors/**/*.scala"/>
-      <exclude name="scala/actors/**/JDK5Scheduler.scala" if="java14"/>
+      <exclude name="scala/actors/ThreadPoolScheduler.scala" if="java14"/>
       <excludesfile name="${nsc.excludes.file}" if="excludes.avail"/>
     </locker>
   <!-- Build compiler -->
@@ -587,6 +587,7 @@ TEST
         <pathelement location="${strap.dir}/lib/actors"/>
       </classpath>
       <include name="scala/actors/**/*.scala"/>
+      <exclude name="scala/actors/ThreadPoolScheduler.scala" if="java14"/>
       <excludesfile name="${nsc.excludes.file}" if="excludes.avail"/>
     </quick>
   <!-- Build compiler -->

src/actors/scala/actors/Channel.scala

@@ -43,7 +43,9 @@ class Channel[Msg] extends InputChannel[Msg] with OutputChannel[Msg] {
   }
 
   /**
-   * Sends <code>msg</code> to this <code>Channel</code>.
+   * Sends a message to this <code>Channel</code>.
+   *
+   * @param  msg the message to be sent
    */
   def !(msg: Msg): unit = {
     receiver ! scala.actors.!(this, msg)
@@ -57,34 +59,62 @@ class Channel[Msg] extends InputChannel[Msg] with OutputChannel[Msg] {
     receiver forward scala.actors.!(this, msg)
   }
 
+  /**
+   * Receives a message from this <code>Channel</code>.
+   *
+   * @param  f    a partial function with message patterns and actions
+   * @return      result of processing the received value
+   */
   def receive[R](f: PartialFunction[Any, R]): R = {
     val C = this.asInstanceOf[Channel[Any]] 
-    // Martin: had to do this to get it to compiler after bug909 fix
     receiver.receive {
       case C ! msg if (f.isDefinedAt(msg)) => f(msg)
     }
   }
 
+  /**
+   * Receives a message from this <code>Channel</code> within a certain
+   * time span.
+   *
+   * @param  msec the time span before timeout
+   * @param  f    a partial function with message patterns and actions
+   * @return      result of processing the received value
+   */
   def receiveWithin[R](msec: long)(f: PartialFunction[Any, R]): R = {
     val C = this.asInstanceOf[Channel[Any]] 
-    // Martin: had to do this to get it to compiler after bug909 fix
     receiver.receiveWithin(msec) {
       case C ! msg if (f.isDefinedAt(msg)) => f(msg)
       case TIMEOUT => f(TIMEOUT)
     }
   }
 
+  /**
+   * Receives a message from this <code>Channel</code>.
+   * <p>
+   * This method never returns. Therefore, the rest of the computation
+   * has to be contained in the actions of the partial function.
+   *
+   * @param  f    a partial function with message patterns and actions
+   */
   def react(f: PartialFunction[Any, Unit]): Nothing = {
     val C = this.asInstanceOf[Channel[Any]] 
-    // Martin: had to do this to get it to compiler after bug909 fix
     receiver.react {
       case C ! msg if (f.isDefinedAt(msg)) => f(msg)
     }
   }
 
+  /**
+   * Receives a message from this <code>Channel</code> within a certain
+   * time span.
+   * <p>
+   * This method never returns. Therefore, the rest of the computation
+   * has to be contained in the actions of the partial function.
+   *
+   * @param  msec the time span before timeout
+   * @param  f    a partial function with message patterns and actions
+   */
   def reactWithin(msec: long)(f: PartialFunction[Any, Unit]): Nothing = {
     val C = this.asInstanceOf[Channel[Any]] 
-    // Martin: had to do this to get it to compiler after bug909 fix
     receiver.reactWithin(msec) {
       case C ! msg if (f.isDefinedAt(msg)) => f(msg)
       case TIMEOUT => f(TIMEOUT)
@@ -92,8 +122,11 @@ class Channel[Msg] extends InputChannel[Msg] with OutputChannel[Msg] {
   }
 
   /**
-   * Sends <code>msg</code> to this <code>Channel</code> and
+   * Sends a message to this <code>Channel</code> and
    * awaits reply.
+   *
+   * @param  msg the message to be sent
+   * @return     the reply
    */
   def !?(msg: Msg): Any = {
     val replyChannel = Actor.self.freshReply()
@@ -103,6 +136,15 @@ class Channel[Msg] extends InputChannel[Msg] with OutputChannel[Msg] {
     }
   }
 
+  /**
+   * Sends a message to this <code>Channel</code> and
+   * awaits reply within a certain time span.
+   *
+   * @param  msec the time span before timeout
+   * @param  msg  the message to be sent
+   * @return      <code>None</code> in case of timeout, otherwise
+   *              <code>Some(x)</code> where <code>x</code> is the reply
+   */
   def !?(msec: long, msg: Msg): Option[Any] = {
     val replyChannel = Actor.self.freshReply()
     receiver ! scala.actors.!(this, msg)

src/actors/scala/actors/Scheduler.scala

@@ -29,7 +29,7 @@ import scala.collection.mutable.{ArrayBuffer, Buffer, HashMap, Queue, Stack, Has
 object Scheduler {
   private var sched: IScheduler =
     {
-      var s: Thread with IScheduler = null
+      var s: IScheduler = null
 
       // Check for JDK version >= 1.5
       var olderThanJDK5 = false
@@ -42,18 +42,8 @@ object Scheduler {
 
       s = if (olderThanJDK5)
         new TickedScheduler
-      else {
-        var corePoolSize = 4
-        var maxPoolSize = 16
-        val prop = java.lang.System.getProperty("actors.corePoolSize")
-        if (null ne prop) {
-          corePoolSize =
-            Integer.parseInt(java.lang.System.getProperty("actors.corePoolSize"))
-          maxPoolSize =
-            Integer.parseInt(java.lang.System.getProperty("actors.maxPoolSize"))
-        }
-        new JDK5Scheduler(corePoolSize, maxPoolSize)
-      }
+      else
+        Class.forName("scala.actors.ThreadPoolScheduler").newInstance().asInstanceOf[IScheduler]
       s.start()
       s
     }
@@ -86,6 +76,7 @@ object Scheduler {
  * @author Philipp Haller
  */
 trait IScheduler {
+  def start(): unit
   def start(task: Reaction): unit
   def execute(task: Reaction): unit
   def getTask(worker: WorkerThread): Runnable
@@ -115,6 +106,8 @@ trait IScheduler {
  * @author Philipp Haller
  */
 class SingleThreadedScheduler extends IScheduler {
+  def start() {}
+
   def start(task: Reaction) {
     // execute task immediately on same thread
     task.run()

src/actors/scala/actors/ThreadPoolScheduler.scala

@@ -13,7 +13,7 @@ import java.util.concurrent.{ThreadPoolExecutor,
                              TimeUnit,
                              RejectedExecutionHandler}
 
-class TaskRejectedHandler(sched: JDK5Scheduler) extends RejectedExecutionHandler {
+class TaskRejectedHandler(sched: ThreadPoolScheduler) extends RejectedExecutionHandler {
   def rejectedExecution(r: Runnable, executor: ThreadPoolExecutor) {
     sched.pendReaction
     r.run()
@@ -26,7 +26,18 @@ class TaskRejectedHandler(sched: JDK5Scheduler) extends RejectedExecutionHandler
  * @version 0.9.2
  * @author Philipp Haller
  */
-class JDK5Scheduler(initCoreSize: int, maxSize: int) extends Thread with IScheduler {
+class ThreadPoolScheduler extends Thread with IScheduler {
+
+  var initCoreSize = 4
+  var maxSize = 16
+
+  val prop = java.lang.System.getProperty("actors.corePoolSize")
+  if (null ne prop) {
+    initCoreSize =
+      Integer.parseInt(java.lang.System.getProperty("actors.corePoolSize"))
+    maxSize =
+      Integer.parseInt(java.lang.System.getProperty("actors.maxPoolSize"))
+  }
 
   /* Note:
    * When using an unbounded queue such as a