From aa4c0389d4f218eecfe7c05ea5596934a33938ad Mon Sep 17 00:00:00 2001
From: hns <hannesw@gmail.com>
Date: Fri, 7 Jun 2002 19:15:51 +0000
Subject: [PATCH] merged in changes from "lazy_typing" branch, prototypes are
 only initialized on demand.

---
 src/helma/framework/core/Application.java     | 123 ++++----
 src/helma/framework/core/Prototype.java       |  49 ++-
 .../framework/core/RequestEvaluator.java      |  89 ++++--
 src/helma/framework/core/Skin.java            |  29 +-
 src/helma/framework/core/TypeManager.java     | 212 ++++---------
 src/helma/framework/core/ZippedAppFile.java   |   8 +
 ...gEnvironment.java => ScriptingEngine.java} |  24 +-
 .../scripting/fesi/FesiEngineFactory.java     |  18 ++
 src/helma/scripting/fesi/FesiEvaluator.java   | 284 ++++++++++++------
 .../fesi/FesiScriptingEnvironment.java        |  85 ------
 10 files changed, 460 insertions(+), 461 deletions(-)
 rename src/helma/scripting/{ScriptingEnvironment.java => ScriptingEngine.java} (59%)
 create mode 100644 src/helma/scripting/fesi/FesiEngineFactory.java
 delete mode 100644 src/helma/scripting/fesi/FesiScriptingEnvironment.java

diff --git a/src/helma/framework/core/Application.java b/src/helma/framework/core/Application.java
index 3356377b..9a6d6ff3 100644
--- a/src/helma/framework/core/Application.java
+++ b/src/helma/framework/core/Application.java
@@ -25,16 +25,13 @@ import java.rmi.server.*;
  * requests from the Web server or XML-RPC port and dispatches them to
  * the evaluators.
  */
-public class Application extends UnicastRemoteObject implements IRemoteApp, IPathElement, IReplicatedApp, Runnable {
+public final class Application extends UnicastRemoteObject implements IRemoteApp, IPathElement, IReplicatedApp, Runnable {
 
     private String name;
     SystemProperties props, dbProps;
     File home, appDir, dbDir;
     protected NodeManager nmgr;
 
-    // the class name of the scripting environment implementation
-    ScriptingEnvironment scriptingEngine;
-
     // the root of the website, if a custom root object is defined.
     // otherwise this is managed by the NodeManager and not cached here.
     Object rootObject = null;
@@ -111,9 +108,6 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
     // Map of extensions allowed for public skins
     Properties skinExtensions;
 
-    // a cache for parsed skin objects
-    public CacheMap skincache = new CacheMap (200, 0.80f);
-
     // DocApplication used for introspection
     public DocApplication docApp;
 
@@ -228,29 +222,29 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
      * Get the application ready to run, initializing the evaluators and type manager.
      */
     public void init () throws DatabaseException, ScriptingException {
-	scriptingEngine = new helma.scripting.fesi.FesiScriptingEnvironment ();
-	scriptingEngine.init (this, props);
-
-	eval = new RequestEvaluator (this);
-	logEvent ("Starting evaluators for "+name);
-	int maxThreads = 12;
-	try {
-	    maxThreads = Integer.parseInt (props.getProperty ("maxThreads"));
-	} catch (Exception ignore) {}
-	freeThreads = new Stack ();
-	allThreads = new Vector ();
-	allThreads.addElement (eval);
-	for (int i=0; i<maxThreads; i++) {
-	    RequestEvaluator ev = new RequestEvaluator (this);
-	    freeThreads.push (ev);
-	    allThreads.addElement (ev);
-	}
-	activeRequests = new Hashtable ();
+	// scriptingEngine = new helma.scripting.fesi.FesiScriptingEnvironment ();
+	// scriptingEngine.init (this, props);
 
 	typemgr = new TypeManager (this);
 	typemgr.createPrototypes ();
 	// logEvent ("Started type manager for "+name);
 
+	// eval = new RequestEvaluator (this);
+	logEvent ("Starting evaluators for "+name);
+	freeThreads = new Stack ();
+	allThreads = new Vector ();
+	// allThreads.addElement (eval);
+	/* int maxThreads = 12;
+	try {
+	    maxThreads = Integer.parseInt (props.getProperty ("maxThreads"));
+	} catch (Exception ignore) {}
+	for (int i=0; i<maxThreads; i++) {
+	    RequestEvaluator ev = new RequestEvaluator (this);
+	    freeThreads.push (ev);
+	    allThreads.addElement (ev);
+	} */
+	activeRequests = new Hashtable ();
+
 	skinmgr = new SkinManager (this);
 
 	rootMapping = getDbMapping ("root");
@@ -267,16 +261,15 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	rewireDbMappings ();
 
 	nmgr = new NodeManager (this, dbDir.getAbsolutePath (), props);
-	
+
 	xmlrpcHandlerName = props.getProperty ("xmlrpcHandlerName", this.name);
 	if (xmlrpc != null)
 	    xmlrpc.addHandler (xmlrpcHandlerName, new XmlRpcInvoker (this));
 
-	// typemgr.start ();
     }
 
     /**
-     *  Create request evaluators and start scheduler and cleanup thread
+     *  Create and start scheduler and cleanup thread
      */
     public void start () {
 	starttime = System.currentTimeMillis();
@@ -308,18 +301,21 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	        ev.stopThread ();
 	    }
 	}
-	
+
 	// remove evaluators
 	allThreads.removeAllElements ();
 	freeThreads = null;
-	
+
 	// shut down node manager and embedded db
 	try {
 	    nmgr.shutdown ();
 	} catch (DatabaseException dbx) {
 	    System.err.println ("Error shutting down embedded db: "+dbx);
 	}
-	
+
+	// null out type manager
+	typemgr = null;
+
 	// stop logs if they exist
 	if (eventLog != null) {
 	    eventLog.close ();
@@ -339,6 +335,20 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	try {
 	    return (RequestEvaluator) freeThreads.pop ();
 	} catch (EmptyStackException nothreads) {
+	    synchronized (this) {
+	        int maxThreads = 12;
+	        try {
+	            maxThreads = Integer.parseInt (props.getProperty ("maxThreads"));
+	        } catch (Exception ignore) {
+	            // property not set, use default value
+	        }
+	        if (allThreads.size() < maxThreads) {
+	            logEvent ("Starting evaluator "+(allThreads.size()+1) +" for application "+name);
+	            RequestEvaluator ev = new RequestEvaluator (this);
+	            allThreads.addElement (ev);
+	            return (ev);
+	        }
+	    }
 	    throw new RuntimeException ("Maximum Thread count reached.");
 	}
     }
@@ -347,8 +357,10 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
      * Returns an evaluator back to the pool when the work is done.
      */
     protected void releaseEvaluator (RequestEvaluator ev) {
-	if (ev != null)
-	    freeThreads.push (ev);
+        if (ev != null) {
+            ev.recycle ();
+            freeThreads.push (ev);
+        }
     }
 
     /**
@@ -435,6 +447,9 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	        // response needs to be closed/encoded before sending it back
 	        try {
 	            res.close (charset);
+	            // reset data fields for garbage collection (may hold references to evaluator)
+	            res.data = null;
+	            req.data = null;
 	        } catch (UnsupportedEncodingException uee) {
 	            logEvent ("Unsupported response encoding: "+uee.getMessage());
 	        }
@@ -442,7 +457,6 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	        res.waitForClose ();
 	    }
 	}
-
 	return res;
     }
 
@@ -845,6 +859,10 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	return debug;
     }
 
+    /**
+     *  Utiliti function invoker for the methods below. This *must* be called 
+     *  by an active RequestEvaluator thread.
+     */
     private Object invokeFunction (Object obj, String func, Object[] args) {
 	Thread thread = Thread.currentThread ();
 	RequestEvaluator reval = null;
@@ -858,13 +876,13 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	    return reval.invokeDirectFunction (obj, func, args);
 	} catch (Exception x) {
 	    if (debug)
-	        System.err.println ("ERROR invoking function "+func+": "+x);
+	        System.err.println ("Error in Application.invokeFunction ("+func+"): "+x);
 	}
 	return null;
     }
 
     //////////////////////////////////////////////////////////////////////////////////////////////////////////
-    ///   The following methods mimic the IPathElement interface. This allows as
+    ///   The following methods mimic the IPathElement interface. This allows us
     ///   to script any Java object: If the object implements IPathElement (as does
     ///   the Node class in Helma's internal objectmodel) then the corresponding
     ///   method is called in the object itself. Otherwise, a corresponding script function
@@ -999,14 +1017,6 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
     }
 
 
-    /**
-     *  Get scripting environment for this application
-     */
-    public ScriptingEnvironment getScriptingEnvironment () {
-	return scriptingEngine;
-    }
-
-
     /**
      * The run method performs periodic tasks like executing the scheduler method and
      * kicking out expired user sessions.
@@ -1014,12 +1024,19 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
     public void run () {
 	long cleanupSleep = 60000;    // thread sleep interval (fixed)
 	long scheduleSleep = 60000;  // interval for scheduler invocation
-	long lastScheduler = 0;
+	long lastScheduler = 0;    // run scheduler immediately
 	long lastCleanup = System.currentTimeMillis ();
 
 	// logEvent ("Starting scheduler for "+name);
 	// as first thing, invoke function onStart in the root object
 
+	eval = new RequestEvaluator (this);
+	allThreads.addElement (eval);
+
+	// read in standard prototypes to make first request go faster
+	typemgr.updatePrototype ("root");
+	typemgr.updatePrototype ("global");
+
 	try {
 	    eval.invokeFunction ((INode) null, "onStart", new Object[0]);
 	} catch (Exception ignore) {
@@ -1032,8 +1049,8 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	    try {
 	        sessionTimeout = Math.max (0, Integer.parseInt (props.getProperty ("sessionTimeout", "30")));
 	    } catch (Exception ignore) {
-	    	System.out.println(ignore.toString());
-	    	}
+	        System.out.println(ignore.toString());
+	    }
 
 	    long now = System.currentTimeMillis ();
 
@@ -1044,9 +1061,12 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	        for (Enumeration e = cloned.elements (); e.hasMoreElements (); ) {
 	            Session session = (Session) e.nextElement ();
 	            if (now - session.lastTouched () > sessionTimeout * 60000) {
-//	                if (session.uid != null) {
-//	FIXME onlogout()!        try {eval.invokeFunction (u, "onLogout", new Object[0]);} catch (Exception ignore) {}
-//	                }
+	                INode usernode = session.getUserNode ();
+	                if (usernode != null) {
+	                    try {
+	                        eval.invokeFunction (usernode, "onLogout", new Object[0]);
+	                    } catch (Exception ignore) {}
+	                }
 	                destroySession(session);
 	            }
 	        }
@@ -1080,10 +1100,7 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	        worker = null;
 	        break;
 	    }
-
-
 	}
-
 	logEvent ("Scheduler for "+name+" exiting");
     }
 
diff --git a/src/helma/framework/core/Prototype.java b/src/helma/framework/core/Prototype.java
index 6a64b5a3..09da43c4 100644
--- a/src/helma/framework/core/Prototype.java
+++ b/src/helma/framework/core/Prototype.java
@@ -13,22 +13,22 @@ import helma.util.Updatable;
 
 
 /**
- * The Prototype class represents JavaScript prototypes defined in HOP
- * applications. This manages a prototypes templates, functions and actions 
+ * The Prototype class represents Script prototypes/type defined in a Helma
+ * application. This class manages a prototypes templates, functions and actions 
  * as well as optional information about the mapping of this type to a 
  * relational database table.
  */
 
 
-public class Prototype {
+public final class Prototype {
 
     String id;
     String name;
     Application app;
     public HashMap templates, functions, actions, skins, updatables;
-    long lastUpdate;
+    long lastUpdate, lastCheck;
 
-    Prototype parent;
+    private Prototype parent;
 
     // Tells us whether this prototype is used to script a generic Java object,
     // as opposed to a Helma objectmodel node object.
@@ -39,7 +39,7 @@ public class Prototype {
 	this.app = app;
 	this.name = name;
 	isJavaPrototype = app.isJavaPrototype (name);
-	lastUpdate = 0; // System.currentTimeMillis ();
+	lastUpdate = lastCheck = 0;
     }
 
     /**
@@ -57,29 +57,7 @@ public class Prototype {
 	// this is not allowed for the hopobject and global prototypes
 	if ("hopobject".equalsIgnoreCase (name) || "global".equalsIgnoreCase (name))
 	    return;
-	    
-	Prototype old = this.parent;
 	this.parent = parent;
-
-	// if parent has changed, update ES-prototypes in request evaluators
-	if (parent != old) {
-	    /* Iterator evals = app.typemgr.getRegisteredRequestEvaluators ();
-	    while (evals.hasNext ()) {
-	        try {
-	            RequestEvaluator reval = (RequestEvaluator) evals.next ();
-	            ObjectPrototype op = reval.getPrototype (getName());
-	            // use hopobject (node) as prototype even if prototype is null -
-	            // this is the case if no hopobject directory exists
-	            ObjectPrototype opp = parent == null ?
-	            	reval.esNodePrototype : reval.getPrototype (parent.getName ());
-	            // don't think this is possible, but check anyway
-	            if (opp == null)
-	                opp = reval.esNodePrototype;
-	            op.setPrototype (opp);
-	        } catch (Exception ignore) {
-	        }
-	    } */
-	}
     }
 
     public Prototype getParentPrototype () {
@@ -125,10 +103,23 @@ public class Prototype {
 	    }
 	}
 	return upd;
-
     }
 
+    public long getLastUpdate () {
+	return lastUpdate;
+    }
 
+    public void markUpdated () {
+	lastUpdate = System.currentTimeMillis ();
+    }
+
+    public long getLastCheck () {
+	return lastCheck;
+    }
+
+    public void markChecked () {
+	lastCheck = System.currentTimeMillis ();
+    }
 
     public String toString () {
 	return "[Prototype "+ app.getName()+"/"+name+"]";
diff --git a/src/helma/framework/core/RequestEvaluator.java b/src/helma/framework/core/RequestEvaluator.java
index 7fe31068..46cbe6b3 100644
--- a/src/helma/framework/core/RequestEvaluator.java
+++ b/src/helma/framework/core/RequestEvaluator.java
@@ -18,11 +18,12 @@ import java.util.*;
  * is killed and an error message is returned.
  */
 
-public class RequestEvaluator implements Runnable {
+public final class RequestEvaluator implements Runnable {
 
 
-    public Application app;
-    protected boolean initialized;
+    public final Application app;
+
+    protected final ScriptingEngine scriptingEngine;
 
     public RequestTrans req;
     public ResponseTrans res;
@@ -44,7 +45,7 @@ public class RequestEvaluator implements Runnable {
     // the object path of the request we're evaluating
     List requestPath;
 
-    // the result of the
+    // the result of the operation
     Object result;
 
     // the exception thrown by the evaluator, if any.
@@ -63,7 +64,7 @@ public class RequestEvaluator implements Runnable {
      */
     public RequestEvaluator (Application app) {
 	this.app = app;
-	initialized = false;
+	scriptingEngine = helma.scripting.fesi.FesiEngineFactory.getEngine (app, this);
     }
 
 
@@ -79,9 +80,6 @@ public class RequestEvaluator implements Runnable {
 
 	    // long startCheck = System.currentTimeMillis ();
 	    app.typemgr.checkPrototypes ();
-	    // evaluators are only initialized as needed, so we need to check that here
-	    // if (!initialized)
-	    //     app.typemgr.initRequestEvaluator (this);
 	    // System.err.println ("Type check overhead: "+(System.currentTimeMillis ()-startCheck)+" millis");
 
 	    // object refs to ressolve request path
@@ -225,13 +223,16 @@ public class RequestEvaluator implements Runnable {
 	                try {
 	                    localrtx.timer.beginEvent (txname+" execute");
 
+	                    // enter execution context
+	                    scriptingEngine.enterContext (globals);
+
 	                    // set the req.action property, cutting off the _action suffix
 	                    req.action = action.substring (0, action.length()-7);
 
 	                    // try calling onRequest() function on object before
 	                    // calling the actual action
 	                    try {
-	                        app.scriptingEngine.invoke (currentElement, "onRequest", new Object[0], globals, this);
+	                        scriptingEngine.invoke (currentElement, "onRequest", new Object[0]);
 	                    } catch (RedirectException redir) {
 	                        throw redir;
 	                    } catch (Exception ignore) {
@@ -239,7 +240,7 @@ public class RequestEvaluator implements Runnable {
 	                    }
 
 	                    // do the actual action invocation
-	                    app.scriptingEngine.invoke (currentElement, action, new Object[0], globals, this);
+	                    scriptingEngine.invoke (currentElement, action, new Object[0]);
 
 	                    localrtx.timer.endEvent (txname+" execute");
 	                } catch (RedirectException redirect) {
@@ -324,6 +325,8 @@ public class RequestEvaluator implements Runnable {
 	            globals.put ("res", res);
 	            globals.put ("app", app);
 
+	            scriptingEngine.enterContext (globals);
+
 	            currentElement = root;
 
 	            if (method.indexOf (".") > -1) {
@@ -343,7 +346,7 @@ public class RequestEvaluator implements Runnable {
 	            String proto = app.getPrototypeName (currentElement);
 	            app.checkXmlRpcAccess (proto, method);
 
-	            result = app.scriptingEngine.invoke (currentElement, method, args, globals, this);
+	            result = scriptingEngine.invoke (currentElement, method, args);
 	            commitTransaction ();
 
 	        } catch (Exception wrong) {
@@ -366,14 +369,12 @@ public class RequestEvaluator implements Runnable {
 
 	        // avoid going into transaction if called function doesn't exist
 	        boolean functionexists = true;
-	        if (thisObject == null) try {
-	            functionexists = app.scriptingEngine.hasFunction (null, method, this);
-			} catch (ScriptingException ignore) {}
+	        functionexists = scriptingEngine.hasFunction (thisObject, method);
 
-	        if (!functionexists)
-	            // global function doesn't exist, nothing to do here.
+	        if (!functionexists) {
+	            // function doesn't exist, nothing to do here.
 	            reqtype = NONE;
-	        else try {
+	        } else try {
 	            localrtx.begin (funcdesc);
 
 	            root = app.getDataRoot ();
@@ -383,7 +384,9 @@ public class RequestEvaluator implements Runnable {
 	            globals.put ("res", res);
 	            globals.put ("app", app);
 
-	            app.scriptingEngine.invoke (thisObject, method, args, globals, this);
+	            scriptingEngine.enterContext (globals);
+
+	            result = scriptingEngine.invoke (thisObject, method, args);
 	            commitTransaction ();
 
 	        } catch (Exception wrong) {
@@ -403,6 +406,9 @@ public class RequestEvaluator implements Runnable {
 
 	    }
 
+	    // exit execution context
+	    scriptingEngine.exitContext ();
+
 	    // make sure there is only one thread running per instance of this class
 	    // if localrtx != rtx, the current thread has been aborted and there's no need to notify
 	    if (localrtx != rtx) {
@@ -454,8 +460,13 @@ public class RequestEvaluator implements Runnable {
 	    // wait for request, max 10 min
 	    wait (1000*60*10);
 	    //  if no request arrived, release ressources and thread
-	    if (reqtype == NONE && rtx == localrtx)
+	    if (reqtype == NONE && rtx == localrtx) {
+	        // comment this in to release not just the thread, but also the scripting engine.
+	        // currently we don't do this because of the risk of memory leaks (objects from
+	        // framework referencing into the scripting engine)
+	        // scriptingEngine = null;
 	        rtx = null;
+	    }
 	} catch (InterruptedException ir) {}
     }
 
@@ -469,13 +480,12 @@ public class RequestEvaluator implements Runnable {
 
 	checkThread ();
 	wait (app.requestTimeout);
- 	if (reqtype != NONE) {
+	if (reqtype != NONE) {
 	    app.logEvent ("Stopping Thread for Request "+app.getName()+"/"+req.path);
 	    stopThread ();
 	    res.reset ();
 	    res.write ("<b>Error in application '"+app.getName()+"':</b> <br><br><pre>Request timed out.</pre>");
 	}
-
 	return res;
     }
 
@@ -505,18 +515,20 @@ public class RequestEvaluator implements Runnable {
 
 	checkThread ();
 	wait (app.requestTimeout);
- 	if (reqtype != NONE) {
+	if (reqtype != NONE) {
 	    stopThread ();
 	}
 
+	// reset res for garbage collection (res.data may hold reference to evaluator)
+	res = null;
 	if (exception != null)
 	    throw (exception);
 	return result;
     }
 
     protected Object invokeDirectFunction (Object obj, String functionName, Object[] args) throws Exception {
-	return app.scriptingEngine.invoke (obj, functionName, args, null, this);
-    } 
+	return scriptingEngine.invoke (obj, functionName, args);
+    }
 
     public synchronized Object invokeFunction (Object object, String functionName, Object[] args)
 		throws Exception {
@@ -532,10 +544,12 @@ public class RequestEvaluator implements Runnable {
 	checkThread ();
 	wait (60000l*15); // give internal call more time (15 minutes) to complete
 
- 	if (reqtype != NONE) {
+	if (reqtype != NONE) {
 	    stopThread ();
 	}
 
+	// reset res for garbage collection (res.data may hold reference to evaluator)
+	res = null;
 	if (exception != null)
 	    throw (exception);
 	return result;
@@ -555,10 +569,12 @@ public class RequestEvaluator implements Runnable {
 	checkThread ();
 	wait (app.requestTimeout);
 
- 	if (reqtype != NONE) {
+	if (reqtype != NONE) {
 	    stopThread ();
 	}
 
+	// reset res for garbage collection (res.data may hold reference to evaluator)
+	res = null;
 	if (exception != null)
 	    throw (exception);
 	return result;
@@ -603,7 +619,18 @@ public class RequestEvaluator implements Runnable {
 	}
     }
 
-
+    /**
+     *  Null out some fields, mostly for the sake of garbage collection.
+     */
+    public void recycle () {
+        res = null;
+        req = null;
+        session = null;
+        args = null;
+        requestPath = null;
+        result = null;
+        exception = null;
+    }
 
     /**
      * Check if an action with a given name is defined for a scripted object. If it is,
@@ -613,12 +640,8 @@ public class RequestEvaluator implements Runnable {
 	if (obj == null)
 	    return null;
 	String act = action == null ? "main_action" : action+"_action";
-	try {
-	    if (app.scriptingEngine.hasFunction (obj, act, this))
-	        return act;
-	} catch (ScriptingException x) {
-	    return null;
-	}
+	if (scriptingEngine.hasFunction (obj, act))
+	    return act;
 	return null;
     }
 
diff --git a/src/helma/framework/core/Skin.java b/src/helma/framework/core/Skin.java
index c4b10e13..7ba781f9 100644
--- a/src/helma/framework/core/Skin.java
+++ b/src/helma/framework/core/Skin.java
@@ -18,19 +18,24 @@ import java.util.*;
  * from the RequestEvaluator object to resolve Macro handlers by type name.
  */
 
-public class Skin {
+public final class Skin {
+
+    private Macro[] parts;
+    private Application app;
+    private char[] source;
+    private int sourceLength;
+    private HashSet sandbox;
 
-    Macro[] parts;
-    Application app;
-    char[] source;
-    int sourceLength;
-    HashSet sandbox;
 
     /**
      * Create a skin without any restrictions on which macros are allowed to be called from it
      */
     public Skin (String content, Application app) {
-	this (content, app, null);
+	this.app = app;
+	sandbox = null;
+	source = content.toCharArray ();
+	sourceLength = source.length;
+	parse ();
     }
 
     /**
@@ -50,8 +55,8 @@ public class Skin {
     public Skin (char[] content, int length, Application app) {
 	this.app = app;
 	this.sandbox = null;
-	this.source = content;
-	this.sourceLength = length;
+	source = content;
+	sourceLength = length;
 	parse ();
     }
 
@@ -315,12 +320,12 @@ public class Skin {
 	            Object v = null;
 	            // remember length of response buffer before calling macro
 	            int oldLength = reval.res.getBufferLength ();
-	            if (app.scriptingEngine.hasFunction (handlerObject, name+"_macro", reval)) {
+	            if (reval.scriptingEngine.hasFunction (handlerObject, name+"_macro")) {
 	                // System.err.println ("Getting macro from function");
-	                v = app.scriptingEngine.invoke (handlerObject, name+"_macro", arguments, null, reval);
+	                v = reval.scriptingEngine.invoke (handlerObject, name+"_macro", arguments);
 	            } else {
 	                // System.err.println ("Getting macro from property");
-	                v = app.scriptingEngine.get (handlerObject, name, reval);
+	                v = reval.scriptingEngine.get (handlerObject, name);
 	            }
 	            // check if macro wrote out to response buffer
 	            int newLength = reval.res.getBufferLength ();
diff --git a/src/helma/framework/core/TypeManager.java b/src/helma/framework/core/TypeManager.java
index 2dd8c0e8..8151986a 100644
--- a/src/helma/framework/core/TypeManager.java
+++ b/src/helma/framework/core/TypeManager.java
@@ -16,7 +16,7 @@ import java.io.*;
  * applications and updates the evaluators if anything has changed.
  */
 
-public class TypeManager {
+public final class TypeManager {
 
     Application app;
     File appDir;
@@ -26,36 +26,23 @@ public class TypeManager {
     long idleSeconds = 120; // if idle for longer than 5 minutes, slow down
     boolean rewire;
 
-    // this contains only those evaluatores which have already been initialized
-    // and thus need to get updates
-    List registeredEvaluators;
-
-
-    static HashSet standardTypes;
-    static {
-	standardTypes = new HashSet ();
-	standardTypes.add ("user");
-	standardTypes.add ("global");
-	standardTypes.add ("root");
-	standardTypes.add ("hopobject");
-    }
-
+    static String[] standardTypes = {"user", "global", "root", "hopobject"};
+ 
     public TypeManager (Application app) {
-	this.app = app;
-	appDir = app.appDir;
-	// make sure the directories for the standard prototypes exist, and lament otherwise
-	if (appDir.list().length == 0) {
-	    for (Iterator it=standardTypes.iterator (); it.hasNext (); ) {
-	        File f = new File (appDir, (String) it.next ());
-	        if (!f.exists() && !f.mkdir ())	
-	            app.logEvent ("Warning: directory "+f.getAbsolutePath ()+" could not be created.");
-	        else if (!f.isDirectory ())
-	            app.logEvent ("Warning: "+f.getAbsolutePath ()+" is not a directory.");
-	    }
-	}
-	prototypes = new HashMap ();
-	zipfiles = new HashMap ();
-	registeredEvaluators = Collections.synchronizedList (new ArrayList ());
+        this.app = app;
+        appDir = app.appDir;
+        // make sure the directories for the standard prototypes exist, and lament otherwise
+        if (appDir.list().length == 0) {
+            for (int i=0; i<standardTypes.length; i++) {
+                File f = new File (appDir, standardTypes[i]);
+                if (!f.exists() && !f.mkdir ())	
+                    app.logEvent ("Warning: directory "+f.getAbsolutePath ()+" could not be created.");
+                else if (!f.isDirectory ())
+                    app.logEvent ("Warning: "+f.getAbsolutePath ()+" is not a directory.");
+            }
+        }
+        prototypes = new HashMap ();
+        zipfiles = new HashMap ();
     }
 
 
@@ -64,7 +51,17 @@ public class TypeManager {
      * compile or evaluate any scripts.
      */
     public void createPrototypes () {
-	check (false);
+        checkFiles ();
+        // check if standard prototypes have been created
+        // if not, create them.
+        for (int i=0; i<standardTypes.length; i++) {
+            String pname = standardTypes[i];
+            if (prototypes.get (pname) == null) {
+                Prototype proto = new Prototype (pname, app);
+                registerPrototype (pname, new File (appDir, pname), proto);
+                prototypes.put (pname, proto);
+            }
+        }
     }
 
 
@@ -73,10 +70,10 @@ public class TypeManager {
      * If so, update prototypes and scripts.
      */
     public synchronized void checkPrototypes () {
-	if (System.currentTimeMillis () - lastCheck  < 500l)
+	if (System.currentTimeMillis () - lastCheck  < 1000l)
 	    return;
 	try {
-	    check (true);
+	    checkFiles ();
 	} catch (Exception ignore) {}
 	lastCheck = System.currentTimeMillis ();
     }
@@ -84,7 +81,7 @@ public class TypeManager {
     /**
      * Run through application's prototype directories and check if anything has been updated.
      */
-    public void check (boolean update) {
+    public void checkFiles () {
 	// long now = System.currentTimeMillis ();
 	// System.out.print ("checking "+Thread.currentThread ());
 	File[] list = appDir.listFiles ();
@@ -96,12 +93,12 @@ public class TypeManager {
 	    if (proto != null) {
 	        // check if existing prototype needs update
 	        // app.logEvent (protoDir.lastModified ());
-	        updatePrototype (filename, list[i], proto);
+	        // updatePrototype (filename, list[i], proto);
 	    } else if (list[i].isDirectory () && isValidTypeName (filename)) {
 	        // leave out ".." and other directories that contain "."
 	        // create new prototype
 	        proto = new Prototype (filename, app);
-	        registerPrototype (filename, list[i], proto, update);
+	        registerPrototype (filename, list[i], proto);
 	        prototypes.put (filename, proto);
 	        // give logger thread a chance to tell what's going on
 	        // Thread.yield();
@@ -121,20 +118,7 @@ public class TypeManager {
 	        zipped.update ();
 	    }
 	}
-	
-	// check if standard prototypes have been created
-	// as a performance hack, we only do this when update is false, i.e. the first time we're called.
-	if (!update) {
-	    for (Iterator it=standardTypes.iterator (); it.hasNext (); ) {
-	        String pname = (String) it.next();
-	        if (prototypes.get (pname) == null) {
-	            Prototype proto = new Prototype (pname, app);
-	            registerPrototype (pname, new File (appDir, pname), proto, false);
-	            prototypes.put (pname, proto);
-	        }
-	    }
-	}
-	
+		
 	if (rewire) {
 	    // there have been changes in the  DbMappings
 	    app.rewireDbMappings ();
@@ -182,7 +166,8 @@ public class TypeManager {
     /**
      *  Create a prototype from a directory containing scripts and other stuff
      */
-    public void registerPrototype (String name, File dir, Prototype proto, boolean update) {
+    public void registerPrototype (String name, File dir, Prototype proto) {
+        // System.err.println ("REGISTER PROTO: "+app.getName()+"/"+name);
         // app.logEvent ("registering prototype "+name);
 
         // show the type checker thread that there has been type activity
@@ -194,84 +179,38 @@ public class TypeManager {
         HashMap nskins = new HashMap ();
         HashMap updatables = new HashMap ();
 
-        if (update) {
-            String list[] = dir.list();
-            for (int i=0; i<list.length; i++) {
-                File tmpfile = new File (dir, list[i]);
-                int dot = list[i].indexOf (".");
-
-                if (dot < 0)
-                    continue;
-
-                String tmpname = list[i].substring(0, dot);
-
-                if (list[i].endsWith (app.templateExtension)) {
-                    try {
-                        Template t = new Template (tmpfile, tmpname, proto);
-                        updatables.put (list[i], t);
-                        ntemp.put (tmpname, t);
-                    } catch (Throwable x) {
-                        app.logEvent ("Error creating prototype: "+x);
-                    }
-
-                } else if (list[i].endsWith (app.scriptExtension) && tmpfile.length () > 0) {
-                    try {
-                        FunctionFile ff = new FunctionFile (tmpfile, tmpname, proto);
-                        updatables.put (list[i], ff);
-                        nfunc.put (tmpname, ff);
-                    } catch (Throwable x) {
-                        app.logEvent ("Error creating prototype: "+x);
-                    }
-
-                } else if (list[i].endsWith (app.actionExtension) && tmpfile.length () > 0) {
-                    try {
-                        ActionFile af = new ActionFile (tmpfile, tmpname, proto);
-                        updatables.put (list[i], af);
-                        nact.put (tmpname, af);
-                    } catch (Throwable x) {
-                        app.logEvent ("Error creating prototype: "+x);
-                    }
-                }  else if (list[i].endsWith (app.skinExtension)) {
-                    try {
-                        SkinFile sf = new SkinFile (tmpfile, tmpname, proto);
-                        updatables.put (list[i], sf);
-                        nskins.put (tmpname, sf);
-                    } catch (Throwable x) {
-                        app.logEvent ("Error creating prototype: "+x);
-                    }
-                }
-            }
-        }
-
         // Create and register type properties file
         File propfile = new File (dir, "type.properties");
         SystemProperties props = new SystemProperties (propfile.getAbsolutePath ());
         DbMapping dbmap = new DbMapping (app, name, props);
         updatables.put ("type.properties", dbmap);
 
-
         proto.templates = ntemp;
         proto.functions = nfunc;
         proto.actions = nact;
         proto.skins = nskins;
         proto.updatables = updatables;
 
-        // init prototype on evaluators that are already initialized.
-        /* Iterator evals = getRegisteredRequestEvaluators ();
-        while (evals.hasNext ()) {
-            RequestEvaluator reval = (RequestEvaluator) evals.next ();
-            proto.initRequestEvaluator (reval);
-        }*/
-        app.scriptingEngine.updatePrototype (proto);
-
+        // app.scriptingEngine.updatePrototype (proto);
     }
 
 
     /**
     * Update a prototype based on the directory which defines it.
     */
-    public void updatePrototype (String name, File dir, Prototype proto) {
+    public void updatePrototype (String name) {
+        // System.err.println ("UPDATE PROTO: "+app.getName()+"/"+name);
+        Prototype proto = getPrototype (name);
+        if (proto == null)
+            return;
+        if (System.currentTimeMillis() - proto.getLastCheck() < 1000)
+            return;
 
+        synchronized (proto) {
+        if (System.currentTimeMillis() - proto.getLastCheck() < 1000)
+            return;
+
+        File dir = new File (appDir, name);
         boolean needsUpdate = false;
         HashSet updatables = null;
 
@@ -290,22 +229,22 @@ public class TypeManager {
         if (proto.lastUpdate < dir.lastModified ()) {
             String[] list = dir.list();
             for (int i=0; i<list.length; i++) {
-	    String fn = list[i];
-	    if (!proto.updatables.containsKey (fn)) {
-	        if (fn.endsWith (app.templateExtension) || fn.endsWith (app.scriptExtension) ||
+                String fn = list[i];
+                if (!proto.updatables.containsKey (fn)) {
+                    if (fn.endsWith (app.templateExtension) || fn.endsWith (app.scriptExtension) ||
 	    	fn.endsWith (app.actionExtension) || fn.endsWith (app.skinExtension) ||
 	    	"type.properties".equalsIgnoreCase (fn)) {
-	            needsUpdate = true;
-	            // updatables.add ("[new:"+proto.getName()+"/"+fn+"]");
-                      }
-	    }
-             }
+                        needsUpdate = true;
+                        // updatables.add ("[new:"+proto.getName()+"/"+fn+"]");
+                    }
+                }
+            }
         }
 
-        if (!needsUpdate)
-	return;
-
-        proto.lastUpdate = System.currentTimeMillis ();
+        if (!needsUpdate) {
+            proto.markChecked ();
+            return;
+        }
 
         // let the thread know we had to do something.
         idleSeconds = 0;
@@ -381,31 +320,12 @@ public class TypeManager {
                 }
             }
         }
-        app.scriptingEngine.updatePrototype (proto);
+        proto.markUpdated();
+
+        } // end of synchronized (proto)
+
+        // app.scriptingEngine.updatePrototype (proto);
     }
 
-
-    /*public void initRequestEvaluator (RequestEvaluator reval) {
-        if (!registeredEvaluators.contains (reval))
-            registeredEvaluators.add (reval);
-        for (Iterator it = prototypes.values().iterator(); it.hasNext(); ) {
-            Prototype p = (Prototype) it.next ();
-            p.initRequestEvaluator (reval);
-        }
-        reval.initialized = true;
-    }
-
-    public void unregisterRequestEvaluator (RequestEvaluator reval) {
-        registeredEvaluators.remove (reval);
-    }
-
-    public Iterator getRegisteredRequestEvaluators () {
-        return registeredEvaluators.iterator ();
-    }
-
-    public int countRegisteredRequestEvaluators () {
-        return registeredEvaluators.size ();
-    } */
-
 }
 
diff --git a/src/helma/framework/core/ZippedAppFile.java b/src/helma/framework/core/ZippedAppFile.java
index f3032629..2812968b 100644
--- a/src/helma/framework/core/ZippedAppFile.java
+++ b/src/helma/framework/core/ZippedAppFile.java
@@ -74,6 +74,8 @@ public class ZippedAppFile implements Updatable {
 	                    // System.err.println ("["+content+"]");
 	                    ActionFile act = new ActionFile (content, name, proto);
 	                    proto.actions.put (name, act);
+	                    // mark prototype as updated
+	                    proto.markUpdated ();
 	                }
 	                else if (fname.endsWith (".hsp")) {
 	                    String name = fname.substring (0, fname.lastIndexOf ("."));
@@ -81,6 +83,8 @@ public class ZippedAppFile implements Updatable {
 	                    // System.err.println ("["+content+"]");
 	                    Template tmp = new Template (content, name, proto);
 	                    proto.templates.put (name, tmp);
+	                    // mark prototype as updated
+	                    proto.markUpdated ();
 	                }
 	                else if (fname.endsWith (".skin")) {
 	                    String name = fname.substring (0, fname.lastIndexOf ("."));
@@ -95,12 +99,16 @@ public class ZippedAppFile implements Updatable {
 	                    // System.err.println ("["+content+"]");
 	                    FunctionFile ff = new FunctionFile (content, name, proto);
 	                    proto.functions.put (name, ff);
+	                    // mark prototype as updated
+	                    proto.markUpdated ();
 	                }
 	                else if ("type.properties".equalsIgnoreCase (fname)) {
 	                    String name = fname.substring (0, fname.lastIndexOf ("."));
 	                    SystemProperties props = new SystemProperties (zip.getInputStream (entry));
 	                    // DbMapping does its own registering, just construct it.
 	                    new DbMapping (app, proto.getName (), props);
+	                    // mark prototype as updated
+	                    proto.markUpdated ();
 	                }
 	            }
 	        }
diff --git a/src/helma/scripting/ScriptingEnvironment.java b/src/helma/scripting/ScriptingEngine.java
similarity index 59%
rename from src/helma/scripting/ScriptingEnvironment.java
rename to src/helma/scripting/ScriptingEngine.java
index 4ded3664..0da2fc7e 100644
--- a/src/helma/scripting/ScriptingEnvironment.java
+++ b/src/helma/scripting/ScriptingEngine.java
@@ -1,4 +1,4 @@
-// ScriptingEnvironment.java
+// ScriptingEngine.java
 // Copyright (c) Hannes Wallnöfer 1998-2001
 
 package helma.scripting;
@@ -13,35 +13,37 @@ import java.io.File;
  * This is the interface that must be implemented to make a scripting environment
  * usable by the Helma application server.
  */
-public interface ScriptingEnvironment {
+public interface ScriptingEngine {
 
     /**
-     * Initialize the environment using the given properties
+     *  This method is called when an execution context for a request
+     *  evaluation is entered. The globals parameter contains the global values
+     *  to be applied during this executino context.
      */
-    public void init (Application app, Properties props) throws ScriptingException;
+    public void enterContext (HashMap globals) throws ScriptingException;
 
     /**
-     * A prototype has been updated and must be re-evaluated.
+     *   This method is called to let the scripting engine know that the current
+     *   execution context has terminated.
      */
-    public void updatePrototype (Prototype prototype);
+    public void exitContext ();
+
 
     /**
      * Invoke a function on some object, using the given arguments and global vars.
      */
-    public Object invoke (Object thisObject, String functionName, Object[] args,
-		HashMap globals, RequestEvaluator reval)
+    public Object invoke (Object thisObject, String functionName, Object[] args)
 		throws ScriptingException;
 
     /**
      *  Get a property on an object
      */
-    public Object get (Object thisObject, String key, RequestEvaluator reval);
+    public Object get (Object thisObject, String key);
 
     /**
      *  Return true if a function by that name is defined for that object.
      */
-    public boolean hasFunction (Object thisObject, String functionName, RequestEvaluator reval)
-		throws ScriptingException;
+    public boolean hasFunction (Object thisObject, String functionName);
 
 }
 
diff --git a/src/helma/scripting/fesi/FesiEngineFactory.java b/src/helma/scripting/fesi/FesiEngineFactory.java
new file mode 100644
index 00000000..476e0a3e
--- /dev/null
+++ b/src/helma/scripting/fesi/FesiEngineFactory.java
@@ -0,0 +1,18 @@
+// FesiEngineFactory.java
+// Copyright (c) Hannes Wallnöfer 2002
+
+package helma.scripting.fesi;
+
+import helma.scripting.*;
+import helma.framework.core.*;
+
+/**
+ *  Factory class for FESI evalator engines.
+ */
+public final class FesiEngineFactory  {
+
+    public static ScriptingEngine getEngine (Application app, RequestEvaluator reval) {
+	return new FesiEvaluator (app, reval);
+    }
+	
+}
diff --git a/src/helma/scripting/fesi/FesiEvaluator.java b/src/helma/scripting/fesi/FesiEvaluator.java
index 284c7568..6a181680 100644
--- a/src/helma/scripting/fesi/FesiEvaluator.java
+++ b/src/helma/scripting/fesi/FesiEvaluator.java
@@ -22,16 +22,16 @@ import Acme.LruHashtable;
  * This is the implementation of ScriptingEnvironment for the FESI EcmaScript interpreter.
  */
 
-public final class FesiEvaluator {
+public final class FesiEvaluator implements ScriptingEngine {
 
     // the application we're running in
-    public Application app;
+    public final Application app;
 
     // The FESI evaluator
-    Evaluator evaluator;
+    final Evaluator evaluator;
    
     // the global object
-    GlobalObject global;
+    final GlobalObject global;
 
     // caching table for JavaScript object wrappers
     LruHashtable wrappercache;
@@ -40,8 +40,8 @@ public final class FesiEvaluator {
     Hashtable prototypes;
 
     // the request evaluator instance owning this fesi evaluator
-    RequestEvaluator reval;
-
+    final RequestEvaluator reval;
+    
     // extensions loaded by this evaluator
     static String[] extensions = new String[] {
 	"FESI.Extensions.BasicIO",
@@ -57,6 +57,7 @@ public final class FesiEvaluator {
     // do lazy cleanup
     Map lastGlobals = null;
 
+
     public FesiEvaluator (Application app, RequestEvaluator reval) {
 	this.app = app;
 	this.reval = reval;
@@ -67,7 +68,7 @@ public final class FesiEvaluator {
 	    evaluator.reval = this;
 	    global = evaluator.getGlobalObject();
 	    for (int i=0; i<extensions.length; i++)
-	        evaluator.addExtension (extensions[i]);
+             evaluator.addExtension (extensions[i]);
 	    HopExtension hopx = new HopExtension (app);
 	    hopx.initializeExtension (this);
 	    MailExtension mailx = (MailExtension) evaluator.addExtension ("helma.scripting.fesi.extensions.MailExtension");
@@ -93,12 +94,66 @@ public final class FesiEvaluator {
 	Collection prototypes = app.getPrototypes();
 	for (Iterator i=prototypes.iterator(); i.hasNext(); ) {
 	    Prototype proto = (Prototype) i.next ();
-	    evaluatePrototype (proto);
+	    initPrototype (proto);
 	}
+	// always fully initialize global prototype, because
+	// we always need it and there's no chance to trigger
+	// creation on demand.
+	getPrototype ("global");
+    }
+
+    void initPrototype (Prototype prototype) {
+        // System.err.println ("FESI INIT PROTO "+prototype);
+	ObjectPrototype op = null;
+
+	// get the prototype's prototype if possible and necessary
+	ObjectPrototype opp = null;
+	Prototype parent = prototype.getParentPrototype ();
+	if (parent != null) {
+	    // see if parent prototype is already registered. if not, register it
+	    opp = getRawPrototype (parent.getName ());
+	    if (opp == null) {
+	        initPrototype (parent);
+	        opp = getRawPrototype (parent.getName ());
+	    }
+	}
+	String name = prototype.getName ();
+	if (!"global".equalsIgnoreCase (name) && !"hopobject".equalsIgnoreCase (name) && opp == null) {
+	    if (app.isJavaPrototype (name))
+	        opp = getRawPrototype ("__javaobject__");
+	    else
+	        opp = getRawPrototype ("hopobject");
+	}
+
+	// if prototype doesn't exist (i.e. is a standard prototype built by HopExtension), create it.
+	op = getRawPrototype (name);
+	if (op == null) {
+	    op = new ObjectPrototype (opp, evaluator);
+	    try {
+	        op.putProperty ("prototypename", new ESString (name), "prototypename".hashCode ());
+	    } catch (EcmaScriptException ignore) {}
+	    putPrototype (name, op);
+	} else {
+	    // set parent prototype just in case it has been changed
+	    op.setPrototype (opp);
+	}
+
+	// Register a constructor for all types except global.
+	// This will first create a new prototyped hopobject and then calls
+                  // the actual (scripted) constructor on it.
+	if (!"global".equalsIgnoreCase (name)) {
+             if (!"root".equalsIgnoreCase (name) && !"user".equalsIgnoreCase (name))
+             try {
+	        FunctionPrototype fp = (FunctionPrototype) evaluator.getFunctionPrototype();
+	        global.putHiddenProperty (name, new NodeConstructor (name, fp, this));
+	    } catch (EcmaScriptException ignore) {}
+	}
+	// app.typemgr.updatePrototype (prototype.getName());
+	// evaluatePrototype (prototype);
     }
 
     void evaluatePrototype (Prototype prototype) {
-
+        // System.err.println ("FESI EVALUATE PROTO "+prototype+" FOR "+this);
 	ObjectPrototype op = null;
 
 	// get the prototype's prototype if possible and necessary
@@ -119,7 +174,6 @@ public final class FesiEvaluator {
 	    else
 	        opp = getPrototype ("hopobject");
 	}
-
 	// if prototype doesn't exist (i.e. is a standard prototype built by HopExtension), create it.
 	op = getPrototype (name);
 	if (op == null) {
@@ -129,18 +183,19 @@ public final class FesiEvaluator {
 	    } catch (EcmaScriptException ignore) {}
 	    putPrototype (name, op);
 	} else {
+                      // reset prototype to original state
+	    resetPrototype (op);
 	    // set parent prototype just in case it has been changed
 	    op.setPrototype (opp);
 	}
 
-	resetPrototype (op);
-
 	// Register a constructor for all types except global.
-	// This will first create a node and then call the actual (scripted) constructor on it.
-	if (!"global".equalsIgnoreCase (name)) {
+	// This will first create a new prototyped hopobject and then calls 
+                  // the actual (scripted) constructor on it.
+	if (!"global".equalsIgnoreCase (name) && !"root".equalsIgnoreCase (name) && !"user".equalsIgnoreCase (name)) {
 	    try {
 	        FunctionPrototype fp = (FunctionPrototype) evaluator.getFunctionPrototype();
-	        evaluator.getGlobalObject().putHiddenProperty (name, new NodeConstructor (name, fp, this));
+	        global.putHiddenProperty (name, new NodeConstructor (name, fp, this));
 	    } catch (EcmaScriptException ignore) {}
 	}
 	for (Iterator it = prototype.functions.values().iterator(); it.hasNext(); ) {
@@ -175,7 +230,6 @@ public final class FesiEvaluator {
 	    String prop = en.nextElement ().toString ();
 	    try {
 	        ESValue esv = op.getProperty (prop, prop.hashCode ());
-	        // System.err.println (protoname+"."+obj+"   ->   "+esv.getClass());
 	        if (esv instanceof ConstructedFunctionObject || esv instanceof FesiActionAdapter.ThrowException)
 	            op.deleteProperty (prop, prop.hashCode());
 	    } catch (Exception x) {}
@@ -183,51 +237,40 @@ public final class FesiEvaluator {
     }
 
 
-
     /**
-     * Invoke a function on some object, using the given arguments and global vars.
+     *  This method is called when an execution context for a request
+     *  evaluation is entered. The globals parameter contains the global values
+     *  to be applied during this executino context.
      */
-    public Object invoke (Object thisObject, String functionName, Object[] args, HashMap globals) throws ScriptingException {
-	ESObject eso = null;
-	if (thisObject == null)
-	    eso = global;
-	else
-	    eso = getElementWrapper (thisObject);
-
-	GlobalObject global = evaluator.getGlobalObject ();
-
-	// if we are provided with global variables to set for this invocation,
-	// remember the global variables before invocation to be able to reset them afterwards.
-	Set globalVariables = null;
-	try {
-	    ESValue[] esv = args == null ? new ESValue[0] : new ESValue[args.length];
-	    for (int i=0; i<esv.length; i++) {
-	        // for java.util.Map objects, we use the special "tight" wrapper
-	        // that makes the Map look like a native object
-	        if (args[i] instanceof Map)
-	            esv[i] = new ESMapWrapper (this, (Map) args[i]);
-	        else
-	            esv[i] = ESLoader.normalizeValue (args[i], evaluator);
-	    }
-
-	    if (globals != null && globals != lastGlobals) {
-	        // remember all global variables before invocation
-	        Set tmpGlobal = new HashSet ();
-	        for (Enumeration en = global.getAllProperties(); en.hasMoreElements(); ) {
-	            tmpGlobal.add (en.nextElement ().toString ());
+    public void enterContext (HashMap globals) throws ScriptingException {
+	// first loop through existing prototypes and update them if necessary
+	for (Enumeration e=prototypes.elements(); e.hasMoreElements(); ) {
+	    TypeInfo info = (TypeInfo) e.nextElement ();
+	    // only update prototype if it has already been initialized. 
+	    // otherwise, this will be done on demand
+	    if (info.lastUpdate > 0) {
+	        Prototype p = app.typemgr.getPrototype (info.protoName);
+	        if (p != null) {
+	            app.typemgr.updatePrototype(info.protoName);
+	            if (p.getLastUpdate () > info.lastUpdate) {
+	                evaluatePrototype(p);
+	                info.lastUpdate = p.getLastUpdate ();
+	            }
 	        }
-	        globalVariables = tmpGlobal;
-
-	        // loop through global vars and set them
-	        for (Iterator i=globals.keySet().iterator(); i.hasNext(); ) {
-	            String k = (String) i.next();
-	            Object v = globals.get (k);
-	            ESValue sv = null;
+	    }
+	}
+	// set globals on the global object
+	if (globals != null && globals != lastGlobals) {
+	    // loop through global vars and set them
+	    for (Iterator i=globals.keySet().iterator(); i.hasNext(); ) {
+	        String k = (String) i.next();
+	        Object v = globals.get (k);
+	        ESValue sv = null;
+	        try {
 	            // we do a lot of extra work to make access to global variables
 	            // comfortable to EcmaScript coders, i.e. we use a lot of custom wrappers
 	            // that expose properties and functions in a special way instead of just going
 	            // with the standard java object wrappers.
-
 	            if (v instanceof Map) {
 	                sv = new ESMapWrapper (this, (Map) v);
 	            } else if ("path".equals (k)) {
@@ -255,9 +298,53 @@ public final class FesiEvaluator {
 	                sv = ESLoader.normalizeValue (v, evaluator);
 	            }
 	            global.putHiddenProperty (k, sv);
+	        } catch (Exception x) {
+	            app.logEvent ("Error setting global variable "+k+": "+x);
 	        }
-	        // remember the globals set on this evaluator
-	        // lastGlobals = globals;
+	    }
+	}
+	// remember the globals set on this evaluator
+	lastGlobals = globals;
+    }
+
+    /**
+     *   This method is called to let the scripting engine know that the current
+     *   execution context has terminated.
+     */
+    public void exitContext () {
+	// loop through previous globals and unset them, if necessary.
+	if (lastGlobals != null) {
+	    for (Iterator i=lastGlobals.keySet().iterator(); i.hasNext(); ) {
+	        String g = (String) i.next ();
+	        try {
+	            global.deleteProperty (g, g.hashCode());
+	        } catch (Exception x) {
+	            System.err.println ("Error resetting global property: "+g);
+	        }
+	    }
+	    lastGlobals = null;
+	}
+    }
+
+
+    /**
+     * Invoke a function on some object, using the given arguments and global vars.
+     */
+    public Object invoke (Object thisObject, String functionName, Object[] args) throws ScriptingException {
+	ESObject eso = null;
+	if (thisObject == null)
+	    eso = global;
+	else
+	    eso = getElementWrapper (thisObject);
+	try {
+	    ESValue[] esv = args == null ? new ESValue[0] : new ESValue[args.length];
+	    for (int i=0; i<esv.length; i++) {
+	        // for java.util.Map objects, we use the special "tight" wrapper
+	        // that makes the Map look like a native object
+	        if (args[i] instanceof Map)
+	            esv[i] = new ESMapWrapper (this, (Map) args[i]);
+	        else
+	            esv[i] = ESLoader.normalizeValue (args[i], evaluator);
 	    }
 	    evaluator.thread = Thread.currentThread ();
 	    ESValue retval =  eso.doIndirectCall (evaluator, eso, functionName, esv);
@@ -276,24 +363,6 @@ public final class FesiEvaluator {
 	        x.printStackTrace ();
 	    }
 	    throw new ScriptingException (msg);
-	} finally {
-	    // remove global variables that have been added during invocation.
-	    // this are typically undeclared variables, and we don't want them to
-	    // endure from one request to the next since this leads to buggy code that
-	    // relies on requests being served by the same evaluator, which is typically the
-	    // case under development conditions but not in deployment.
-	    if (globalVariables != null) {
-	        for (Enumeration en = global.getAllProperties(); en.hasMoreElements(); ) {
-	            String g = en.nextElement ().toString ();
-	            try {
-	                if (!globalVariables.contains (g) &&
-				!(global.getProperty (g, g.hashCode()) instanceof BuiltinFunctionObject))
-	                    global.deleteProperty (g, g.hashCode());
-	            } catch (Exception x) {
-	                System.err.println ("Error resetting global property: "+g);
-	            }
-	        }
-	    }
 	}
     }
 
@@ -303,13 +372,11 @@ public final class FesiEvaluator {
      * is a java object) with that name.
      */
     public boolean hasFunction (Object obj, String fname) {
-	ESObject eso = null;
-	if (obj == null)
-	    eso = evaluator.getGlobalObject ();
-	else
-	    eso = getElementWrapper (obj);
+	// System.err.println ("HAS_FUNC: "+fname);
+	String protoname = app.getPrototypeName (obj);
 	try {
-	    ESValue func = eso.getProperty (fname, fname.hashCode());
+	    ObjectPrototype op = getPrototype (protoname);
+	    ESValue func = op.getProperty (fname, fname.hashCode());
 	    if (func != null && func instanceof FunctionPrototype)
 	        return true;
 	} catch (EcmaScriptException esx) {
@@ -324,7 +391,7 @@ public final class FesiEvaluator {
      * Check if an object has a defined property (public field if it
      * is a java object) with that name.
      */
-    public Object getProperty (Object obj, String propname) {
+    public Object get (Object obj, String propname) {
 	if (obj == null || propname == null)
 	    return null;
 
@@ -333,7 +400,7 @@ public final class FesiEvaluator {
 		"password".equalsIgnoreCase (propname))
 	    return "[macro access to password property not allowed]";
 
-	// if this is a HopObject, check if the property is defined
+                  // if this is a HopObject, check if the property is defined
 	// in the type.properties db-mapping.
 	if (obj instanceof INode) {
 	    DbMapping dbm = app.getDbMapping (prototypeName);
@@ -372,13 +439,37 @@ public final class FesiEvaluator {
 	return app;
     }
 
+
     /**
-     *  Get the object prototype for a prototype name
+     * Get a raw prototype, i.e. in potentially unfinished state
+     * without checking if it needs to be updated.
+    */
+    private ObjectPrototype getRawPrototype (String protoName) {
+        if (protoName == null)
+            return null;
+        TypeInfo info = (TypeInfo) prototypes.get (protoName);
+        return info == null? null : info.objectPrototype;
+    }
+
+    /**
+     *  Get the object prototype for a prototype name and initialize/update it
+     *  if necessary.
      */
     public ObjectPrototype getPrototype (String protoName) {
         if (protoName == null)
             return null;
-        return (ObjectPrototype) prototypes.get (protoName);
+        TypeInfo info = (TypeInfo) prototypes.get (protoName);
+        if (info != null && info.lastUpdate == 0) {
+            Prototype p = app.typemgr.getPrototype (protoName);
+            if (p != null) {
+                app.typemgr.updatePrototype(protoName);
+                if (p.getLastUpdate () > info.lastUpdate) {
+                    info.lastUpdate = p.getLastUpdate ();
+                    evaluatePrototype(p);
+                }
+            }
+        }
+        return info == null? null : info.objectPrototype;
     }
 
     /**
@@ -386,7 +477,7 @@ public final class FesiEvaluator {
      */
     public void putPrototype (String protoName, ObjectPrototype op) {
         if (protoName != null && op != null)
-            prototypes.put (protoName, op);
+            prototypes.put (protoName, new TypeInfo (op, protoName));
     }
 
 
@@ -418,7 +509,7 @@ public final class FesiEvaluator {
 
 	// Gotta find out the prototype name to use for this object...
 	String prototypeName = app.getPrototypeName (e);
-
+        
 	ObjectPrototype op = getPrototype (prototypeName);
 
 	if (op == null)
@@ -430,7 +521,7 @@ public final class FesiEvaluator {
 
 
     /**
-     *  Get a script wrapper for an implemntation of helma.objectmodel.INode
+     *  Get a script wrapper for an instance of helma.objectmodel.INode
      */
     public ESNode getNodeWrapper (INode n) {
         // FIXME: should this return ESNull.theNull?
@@ -440,6 +531,7 @@ public final class FesiEvaluator {
         ESNode esn = (ESNode) wrappercache.get (n);
         if (esn == null || esn.getNode() != n) {
             String protoname = n.getPrototype ();
+
             ObjectPrototype op = null;
 
             // set the DbMapping of the node according to its prototype.
@@ -511,15 +603,11 @@ public final class FesiEvaluator {
 	updateEvaluator (prototype, reader, es);
     }
 
-    public  synchronized void updateEvaluator (Prototype prototype, Reader reader, EvaluationSource source) {
-
+    private  synchronized void updateEvaluator (Prototype prototype, Reader reader, EvaluationSource source) {
         try {
-
             ObjectPrototype op = getPrototype (prototype.getName());
-
             // do the update, evaluating the file
             evaluator.evaluate(reader, op, source, false);
-
         } catch (Throwable e) {
             app.logEvent ("Error parsing function file "+source+": "+e);
         } finally {
@@ -532,4 +620,16 @@ public final class FesiEvaluator {
     }
 
 
+    class TypeInfo {
+
+        ObjectPrototype objectPrototype;
+        long lastUpdate = 0;
+        String protoName;
+
+        public TypeInfo (ObjectPrototype op, String name) {
+            objectPrototype = op;
+            protoName = name;
+        }
+    }
+
 }
diff --git a/src/helma/scripting/fesi/FesiScriptingEnvironment.java b/src/helma/scripting/fesi/FesiScriptingEnvironment.java
deleted file mode 100644
index 6e840f28..00000000
--- a/src/helma/scripting/fesi/FesiScriptingEnvironment.java
+++ /dev/null
@@ -1,85 +0,0 @@
-// FesiScriptingEnvironment.java
-// Copyright (c) Hannes Wallnöfer 2002
-
-package helma.scripting.fesi;
-
-import helma.scripting.*;
-import helma.framework.core.*;
-import java.util.*;
-import java.io.File;
-import FESI.Data.*;
-import FESI.Interpreter.*;
-import FESI.Exceptions.*;
-
-/**
- * This is the implementation of ScriptingEnvironment for the FESI EcmaScript interpreter.
- */
-public final class FesiScriptingEnvironment implements ScriptingEnvironment {
-
-    Application app;
-    Properties props;
-    HashMap evaluators;
-
-    /**
-     * Initialize the environment using the given properties
-     */
-    public void init (Application app, Properties props) throws ScriptingException {
-	this.app = app;
-	this.props = props;
-	evaluators = new HashMap ();
-    }
-
-
-    /**
-     * A prototype has been updated and must be re-evaluated.
-     */
-    public void updatePrototype (Prototype prototype) {
-	for (Iterator i = evaluators.values().iterator(); i.hasNext(); ) {
-	    FesiEvaluator fesi = (FesiEvaluator) i.next();
-	    fesi.evaluatePrototype (prototype);
-	}
-    }
-
-    /**
-     * Invoke a function on some object, using the given arguments and global vars.
-     */
-    public Object invoke (Object thisObject, String functionName, Object[] args,
-			HashMap globals, RequestEvaluator reval)
-			throws ScriptingException {
-	// check if there is already a FesiEvaluator for this RequestEvaluator.
-	// if not, create one.
-	FesiEvaluator fesi = getEvaluator (reval);
-	return fesi.invoke (thisObject, functionName, args, globals);
-    }
-
-    /**
-     *  Get a property on an object
-     */
-    public Object get (Object thisObject, String key, RequestEvaluator reval) {
-	FesiEvaluator fesi = getEvaluator (reval);
-	return fesi.getProperty (thisObject, key);
-    }
-
-    /**
-     *  Return true if a function by that name is defined for that object.
-     */
-    public boolean hasFunction (Object thisObject, String functionName, RequestEvaluator reval)
-			throws ScriptingException {
-	FesiEvaluator fesi = getEvaluator (reval);
-	return fesi.hasFunction (thisObject, functionName);
-    }
-
-
-    Collection getEvaluators () {
-	return evaluators.values();
-    }
-
-    private FesiEvaluator getEvaluator (RequestEvaluator reval) {
-	FesiEvaluator fesi = (FesiEvaluator) evaluators.get (reval);
-	if (fesi == null) {
-	    fesi = new FesiEvaluator (app, reval);
-	    evaluators.put (reval, fesi);
-	}
-	return fesi;
-    }
-}