Invoker refactoring.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@3041 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/presents/server/ClientResolver.java

@@ -1,10 +1,11 @@
 //
-// $Id: ClientResolver.java,v 1.5 2004/06/13 08:51:57 mdb Exp $
+// $Id: ClientResolver.java,v 1.6 2004/06/29 03:22:22 mdb Exp $
 
 package com.threerings.presents.server;
 
 import java.util.ArrayList;
 
+import com.samskivert.util.Invoker;
 import com.threerings.util.Name;
 
 import com.threerings.presents.Log;
@@ -12,7 +13,6 @@ import com.threerings.presents.data.ClientObject;
 import com.threerings.presents.dobj.DObject;
 import com.threerings.presents.dobj.ObjectAccessException;
 import com.threerings.presents.dobj.Subscriber;
-import com.threerings.presents.util.Invoker;
 
 /**
  * Used to resolve client data when a user starts a session (or when some

src/java/com/threerings/presents/server/PresentsDObjectMgr.java

@@ -1,5 +1,5 @@
 //
-// $Id: PresentsDObjectMgr.java,v 1.42 2004/02/21 02:18:56 mdb Exp $
+// $Id: PresentsDObjectMgr.java,v 1.43 2004/06/29 03:22:22 mdb Exp $
 
 package com.threerings.presents.server;
 
@@ -12,6 +12,7 @@ import sun.misc.Perf;
 
 import com.samskivert.util.HashIntMap;
 import com.samskivert.util.Histogram;
+import com.samskivert.util.Invoker;
 import com.samskivert.util.Queue;
 import com.samskivert.util.SortableArrayList;
 import com.samskivert.util.StringUtil;
@@ -34,7 +35,8 @@ import com.threerings.presents.dobj.*;
  * requested to shut down.
  */
 public class PresentsDObjectMgr
-    implements RootDObjectManager, PresentsServer.Reporter
+    implements RootDObjectManager, Invoker.ResultReceiver,
+               PresentsServer.Reporter
 {
     /**
      * Creates the dobjmgr and prepares it for operation.

src/java/com/threerings/presents/server/PresentsInvoker.java

@@ -0,0 +1,160 @@
+//
+// $Id: PresentsInvoker.java,v 1.1 2004/06/29 03:22:22 mdb Exp $
+
+package com.threerings.presents.server;
+
+import java.util.Iterator;
+
+import com.samskivert.util.Histogram;
+import com.samskivert.util.Invoker;
+import com.samskivert.util.StringUtil;
+
+import com.threerings.presents.Log;
+
+/**
+ * Extends the generic {@link Invoker} and integrates it a bit more into
+ * the Presents system.
+ */
+public class PresentsInvoker extends Invoker
+    implements PresentsServer.Reporter
+{
+    /**
+     * Creates an invoker that will post results to the supplied
+     * distributed object manager.
+     */
+    public PresentsInvoker (PresentsDObjectMgr omgr)
+    {
+        super("presents.Invoker", omgr);
+        _omgr = omgr;
+        if (PERF_TRACK) {
+            PresentsServer.registerReporter(this);
+        }
+    }
+
+    /**
+     * Will do a sophisticated shutdown of both itself and the DObjectManager
+     * thread.
+     */
+    public void shutdown ()
+    {
+        _queue.append(new ShutdownUnit());
+    }
+
+    // documentation inherited from interface
+    public void appendReport (StringBuffer buffer, long now, long sinceLast)
+    {
+        buffer.append("* presents.util.Invoker:\n");
+        buffer.append("- Units executed: ").append(_unitsRun).append("\n");
+        _unitsRun = 0;
+        for (Iterator iter = _tracker.keySet().iterator(); iter.hasNext(); ) {
+            Class key = (Class)iter.next();
+            Histogram histo = (Histogram)_tracker.get(key);
+            buffer.append("  ");
+            buffer.append(StringUtil.shortClassName(key)).append(": ");
+            buffer.append(histo.summarize()).append("\n");
+            histo.clear();
+        }
+    }
+
+    /**
+     * This unit gets posted back and forth between the invoker and DObjectMgr
+     * until both of their queues are empty and they can both be safely
+     * shutdown.
+     */
+    protected class ShutdownUnit extends Unit
+    {
+        // run on the invoker thread
+        public boolean invoke ()
+        {
+            if (checkLoops()) {
+                return false;
+
+            // if the invoker queue is not empty, we put ourselves back on it
+            } else if (_queue.hasElements()) {
+                _loopCount++;
+                postUnit(this);
+                return false;
+
+            } else {
+                // the invoker is empty, let's go over to the omgr
+                _loopCount = 0;
+                _passCount++;
+                return true;
+            }
+        }
+
+        // run on the dobj thread
+        public void handleResult ()
+        {
+            if (checkLoops()) {
+                return;
+
+            // if the queue isn't empty, re-post
+            } else if (!_omgr.queueIsEmpty()) {
+                _loopCount++;
+                _omgr.postUnit(this);
+
+            // if the invoker still has stuff and we're still under the pass
+            // limit, go ahead and pass it back to the invoker
+            } else if (_queue.hasElements() && (_passCount < MAX_PASSES)) {
+                // pass the buck back to the invoker
+                _loopCount = 0;
+                postUnit(this);
+
+            } else {
+                // otherwise end it, and complain if we're ending it
+                // because of passes
+                if (_passCount >= MAX_PASSES) {
+                    Log.warning("Shutdown Unit passed 50 times without " +
+                        "finishing, shutting down harshly.");
+                }
+                doShutdown();
+            }
+        }
+
+        /**
+         * Check to make sure we haven't looped too many times.
+         */
+        protected boolean checkLoops ()
+        {
+            if (_loopCount > MAX_LOOPS) {
+                Log.warning("Shutdown Unit looped on one thread 10000 times " +
+                    "without finishing, shutting down harshly.");
+                doShutdown();
+                return true;
+            }
+
+            return false;
+        }
+
+        /**
+         * Do the actual shutdown.
+         */
+        protected void doShutdown ()
+        {
+            _omgr.harshShutdown(); // end the dobj thread
+
+            // end the invoker thread
+            postUnit(new Unit() {
+                public boolean invoke () {
+                    _running = false;
+                    return false;
+                }
+            });
+        }
+
+        /** The number of times we've been passed to the object manager. */
+        protected int _passCount = 0;
+
+        /** How many times we've looped on the thread we're currently on. */
+        protected int _loopCount = 0;
+
+        /** The maximum number of passes we allow before just ending things. */
+        protected static final int MAX_PASSES = 50;
+
+        /** The maximum number of loops we allow before just ending things. */
+        protected static final int MAX_LOOPS = 10000;
+    }
+
+    protected PresentsDObjectMgr _omgr;
+}

src/java/com/threerings/presents/server/PresentsServer.java

@@ -1,5 +1,5 @@
 //
-// $Id: PresentsServer.java,v 1.40 2004/06/03 09:03:06 mdb Exp $
+// $Id: PresentsServer.java,v 1.41 2004/06/29 03:22:22 mdb Exp $
 
 package com.threerings.presents.server;
 
@@ -16,7 +16,6 @@ import com.threerings.presents.Log;
 import com.threerings.presents.client.Client;
 import com.threerings.presents.server.net.ConnectionManager;
 import com.threerings.presents.server.util.SafeInterval;
-import com.threerings.presents.util.Invoker;
 
 /**
  * The presents server provides a central point of access to the various
@@ -75,7 +74,7 @@ public class PresentsServer
     /** This is used to invoke background tasks that should not be allowed
      * to tie up the distributed object manager thread. This is generally
      * used to talk to databases and other (relatively) slow entities. */
-    public static Invoker invoker;
+    public static PresentsInvoker invoker;
 
     /**
      * Initializes all of the server services and prepares for operation.
@@ -96,7 +95,7 @@ public class PresentsServer
         omgr = new PresentsDObjectMgr();
 
         // create and start up our invoker
-        invoker = new Invoker(omgr);
+        invoker = new PresentsInvoker(omgr);
         invoker.start();
 
         // create our connection manager

src/java/com/threerings/presents/util/Invoker.java

@@ -1,314 +0,0 @@
-//
-// $Id: Invoker.java,v 1.15 2004/06/13 08:03:45 mdb Exp $
-
-package com.threerings.presents.util;
-
-import java.util.HashMap;
-import java.util.Iterator;
-
-import com.samskivert.util.Histogram;
-import com.samskivert.util.LoopingThread;
-import com.samskivert.util.Queue;
-import com.samskivert.util.StringUtil;
-
-import com.threerings.presents.Log;
-import com.threerings.presents.server.PresentsDObjectMgr;
-import com.threerings.presents.server.PresentsServer.Reporter;
-import com.threerings.presents.server.PresentsServer;
-
-/**
- * The invoker is used to invoke self-contained units of code on an
- * invoking thread. Each invoker is associated with its own thread and
- * that thread is used to invoke all of the units posted to that invoker
- * in the order in which they were posted. The invoker also provides a
- * convenient mechanism for processing the result of an invocation back on
- * the dobjmgr thread.
- *
- * <p> The invoker is a useful tool for services that need to block and
- * therefore cannot be run on the distributed object thread. For example,
- * a user of the Presents system might provide an invoker on which to run
- * database queries.
- *
- * <p> Bear in mind that each invoker instance runs units on its own
- * thread and care must be taken to ensure that code running on separate
- * invokers properly synchronizes access to shared information. Where
- * possible, complete isolation of the services provided by a particular
- * invoker is desirable.
- */
-public class Invoker extends LoopingThread
-    implements Reporter
-{
-    /**
-     * The unit encapsulates a unit of executable code that will be run on
-     * the invoker thread. It also provides facilities for additional code
-     * to be run on the dobjmgr thread once the primary code has completed
-     * on the invoker thread.
-     */
-    public static abstract class Unit implements Runnable
-    {
-        /** The default constructor. */
-        public Unit () {}
-
-        /** Creates an invoker unit which will report the supplied name in
-         * {@link #toString}. */
-        public Unit (String name)
-        {
-            _name = name;
-        }
-
-        /**
-         * This method is called on the invoker thread and should be used
-         * to perform the primary function of the unit. It can return true
-         * to cause the <code>handleResult</code> method to be
-         * subsequently invoked on the dobjmgr thread (generally to allow
-         * the results of the invocation to be acted upon back in the
-         * context of the distributed object world) or false to indicate
-         * that no further processing should be performed.
-         *
-         * <p> Note that an invocation unit can do things like post events
-         * from the invoker thread (which includes modification of
-         * distributed object fields) and need not jump over to the
-         * dobjmgr thread to do so. However, it cannot <em>read</em>
-         * distributed object fields from the invoker thread. Any field
-         * values needed during the course of the invocation should be
-         * provided from the dobjmgr thread at the time that the
-         * invocation unit is created and posted.
-         *
-         * @return true if the <code>handleResult</code> method should be
-         * invoked on the dobjmgr thread, false if not.
-         */
-        public abstract boolean invoke ();
-
-        /**
-         * Invocation unit implementations can implement this function to
-         * perform any post-unit-invocation processing back on the dobjmgr
-         * thread. It will be invoked if <code>invoke</code> returns true.
-         */
-        public void handleResult ()
-        {
-            // do nothing by default
-        }
-
-        // we want to be a runnable to make the dobjmgr happy, but we'd
-        // like for invocation unit implementations to be able to put
-        // their result handling code into an aptly named method
-        public void run ()
-        {
-            handleResult();
-        }
-
-        /** Returns the name of this invoker. */
-        public String toString ()
-        {
-            return _name;
-        }
-
-        protected String _name = "Unknown";
-    }
-
-    /**
-     * Creates an invoker that will post results to the supplied
-     * distributed object manager.
-     */
-    public Invoker (PresentsDObjectMgr omgr)
-    {
-        super("presents.Invoker");
-        _omgr = omgr;
-        if (PERF_TRACK) {
-            PresentsServer.registerReporter(this);
-        }
-    }
-
-    /**
-     * Posts a unit to this invoker for subsequent invocation on the
-     * invoker's thread.
-     */
-    public void postUnit (Unit unit)
-    {
-        // simply append it to the queue
-        _queue.append(unit);
-    }
-
-    // documentation inherited
-    public void iterate ()
-    {
-        // pop the next item off of the queue
-        Unit unit = (Unit) _queue.get();
-
-        long start;
-        if (PERF_TRACK) {
-            start = System.currentTimeMillis();
-            _unitsRun++;
-        }
-
-        try {
-            if (unit.invoke()) {
-                // if it returned true, we post it to the dobjmgr
-                // thread to invoke the result processing
-                _omgr.postUnit(unit);
-            }
-
-            // track some performance metrics
-            if (PERF_TRACK) {
-                long duration = System.currentTimeMillis() - start;
-                Object key = unit.getClass();
-                Histogram histo = (Histogram)_tracker.get(key);
-                if (histo == null) {
-                    // track in buckets of 50ms up to 500ms
-                    _tracker.put(key, histo = new Histogram(0, 50, 10));
-                }
-                histo.addValue((int)duration);
-
-                // report long runners
-                if (duration > 500L) {
-                    Log.warning("Invoker unit ran for '" + duration + "ms: " +
-                                unit + "' (" + key + ").");
-                }
-            }
-
-        } catch (Exception e) {
-            Log.warning("Invocation unit failed [unit=" + unit + "].");
-            Log.logStackTrace(e);
-        }
-    }
-
-    /**
-     * Will do a sophisticated shutdown of both itself and the DObjectManager
-     * thread.
-     */
-    public void shutdown ()
-    {
-        _queue.append(new ShutdownUnit());
-    }
-
-    // documentation inherited from interface
-    public void appendReport (StringBuffer buffer, long now, long sinceLast)
-    {
-        buffer.append("* presents.util.Invoker:\n");
-        buffer.append("- Units executed: ").append(_unitsRun).append("\n");
-        _unitsRun = 0;
-        for (Iterator iter = _tracker.keySet().iterator(); iter.hasNext(); ) {
-            Class key = (Class)iter.next();
-            Histogram histo = (Histogram)_tracker.get(key);
-            buffer.append("  ");
-            buffer.append(StringUtil.shortClassName(key)).append(": ");
-            buffer.append(histo.summarize()).append("\n");
-            histo.clear();
-        }
-    }
-
-    /**
-     * This unit gets posted back and forth between the invoker and DObjectMgr
-     * until both of their queues are empty and they can both be safely
-     * shutdown.
-     */
-    protected class ShutdownUnit extends Unit
-    {
-        // run on the invoker thread
-        public boolean invoke ()
-        {
-            if (checkLoops()) {
-                return false;
-
-            // if the invoker queue is not empty, we put ourselves back on it
-            } else if (_queue.hasElements()) {
-                _loopCount++;
-                postUnit(this);
-                return false;
-
-            } else {
-                // the invoker is empty, let's go over to the omgr
-                _loopCount = 0;
-                _passCount++;
-                return true;
-            }
-        }
-
-        // run on the dobj thread
-        public void handleResult ()
-        {
-            if (checkLoops()) {
-                return;
-
-            // if the queue isn't empty, re-post
-            } else if (!_omgr.queueIsEmpty()) {
-                _loopCount++;
-                _omgr.postUnit(this);
-
-            // if the invoker still has stuff and we're still under the pass
-            // limit, go ahead and pass it back to the invoker
-            } else if (_queue.hasElements() && (_passCount < MAX_PASSES)) {
-                // pass the buck back to the invoker
-                _loopCount = 0;
-                postUnit(this);
-
-            } else {
-                // otherwise end it, and complain if we're ending it
-                // because of passes
-                if (_passCount >= MAX_PASSES) {
-                    Log.warning("Shutdown Unit passed 50 times without " +
-                        "finishing, shutting down harshly.");
-                }
-                doShutdown();
-            }
-        }
-
-        /**
-         * Check to make sure we haven't looped too many times.
-         */
-        protected boolean checkLoops ()
-        {
-            if (_loopCount > MAX_LOOPS) {
-                Log.warning("Shutdown Unit looped on one thread 10000 times " +
-                    "without finishing, shutting down harshly.");
-                doShutdown();
-                return true;
-            }
-
-            return false;
-        }
-
-        /**
-         * Do the actual shutdown.
-         */
-        protected void doShutdown ()
-        {
-            _omgr.harshShutdown(); // end the dobj thread
-
-            // end the invoker thread
-            postUnit(new Unit() {
-                public boolean invoke () {
-                    _running = false;
-                    return false;
-                }
-            });
-        }
-
-        /** The number of times we've been passed to the object manager. */
-        protected int _passCount = 0;
-
-        /** How many times we've looped on the thread we're currently on. */
-        protected int _loopCount = 0;
-
-        /** The maximum number of passes we allow before just ending things. */
-        protected static final int MAX_PASSES = 50;
-
-        /** The maximum number of loops we allow before just ending things. */
-        protected static final int MAX_LOOPS = 10000;
-    }
-
-    /** The invoker's queue of units to be executed. */
-    protected Queue _queue = new Queue();
-
-    /** The object manager with which we're working. */
-    protected PresentsDObjectMgr _omgr;
-
-    /** Tracks the counts of invocations by unit's class. */
-    protected HashMap _tracker = new HashMap();
-
-    /** The total number of invoker units run since the last report. */
-    protected int _unitsRun;
-
-    /** Whether or not to track invoker unit performance. */
-    protected static final boolean PERF_TRACK = true;
-}

src/java/com/threerings/whirled/server/SceneManager.java

@@ -1,13 +1,13 @@
 //
-// $Id: SceneManager.java,v 1.17 2004/05/19 22:09:04 ray Exp $
+// $Id: SceneManager.java,v 1.18 2004/06/29 03:22:22 mdb Exp $
 
 package com.threerings.whirled.server;
 
 import com.samskivert.io.PersistenceException;
+import com.samskivert.util.Invoker;
 
 import com.threerings.crowd.server.PlaceManager;
 import com.threerings.presents.server.PresentsServer;
-import com.threerings.presents.util.Invoker;
 
 import com.threerings.whirled.Log;
 import com.threerings.whirled.data.Scene;

src/java/com/threerings/whirled/server/SceneRegistry.java

@@ -1,12 +1,12 @@
 //
-// $Id: SceneRegistry.java,v 1.22 2004/02/25 14:50:28 mdb Exp $
+// $Id: SceneRegistry.java,v 1.23 2004/06/29 03:22:22 mdb Exp $
 
 package com.threerings.whirled.server;
 
 import java.util.ArrayList;
 
 import com.samskivert.util.HashIntMap;
-import com.threerings.presents.util.Invoker;
+import com.samskivert.util.Invoker;
 
 import com.threerings.presents.server.InvocationManager;