* Consider conditional GET headers in RequestTrans.equals(). This fixes a bug

where Mozilla/Firefox displayed an empty page when fetching the same page
  with different headers within a short timeframe.
* Fix Last-Modified handler heading which was broken in more than one way.
* Don't generate ETag headers for error pages.
* Rename ResponseTrans.writeErrorReport() to reportError().
* Set response status to 500 (internal server error) in ResponseTrans.reportError().

src/helma/framework/RequestTrans.java

@@ -56,7 +56,7 @@ public class RequestTrans implements Serializable {
     private String session;
 
     // the map of form and cookie data
-    private final Map values;
+    private final Map values = new SystemMap();
     
     // the HTTP request method
     private String method;
@@ -65,7 +65,7 @@ public class RequestTrans implements Serializable {
     private long ifModifiedSince = -1;
 
     // set of ETags the client sent with If-None-Match header
-    private Set etags;
+    private final Set etags = new HashSet();
 
     // when was execution started on this request?
     private final long startTime;
@@ -83,7 +83,6 @@ public class RequestTrans implements Serializable {
         this.path = path;
         this.request = null;
         this.response = null;
-        values = new SystemMap();
         startTime = System.currentTimeMillis();
     }
 
@@ -96,7 +95,6 @@ public class RequestTrans implements Serializable {
         this.request = request;
         this.response = response;
         this.path = path;
-        values = new SystemMap();
         startTime = System.currentTimeMillis();
     }
 
@@ -166,25 +164,33 @@ public class RequestTrans implements Serializable {
      *  detect multiple identic requests.
      */
     public int hashCode() {
-        if (session == null || path == null)
+        if (session == null || path == null) {
             return super.hashCode();
-        return 17 + (37 * session.hashCode()) +
+        } else {
-                    (37 * path.hashCode());
+            return 17 + (37 * session.hashCode()) +
+                        (37 * path.hashCode());
+        }
     }
 
     /**
-     * A request is considered equal to another one if it has the same user, path,
+     * A request is considered equal to another one if it has the same method,
-     * and request data. This is used to evaluate multiple simultanous requests only once
+     * path, session, request data, and conditional get data. This is used to
+     * evaluate multiple simultanous identical requests only once.
      */
     public boolean equals(Object what) {
-        try {
+        if (what instanceof RequestTrans) {
-            RequestTrans other = (RequestTrans) what;
+            if (session == null || path == null) {
-
+                return super.equals(what);
-            return (session.equals(other.session) && path.equalsIgnoreCase(other.path) &&
+            } else {
-                   values.equals(other.getRequestData()));
+                RequestTrans other = (RequestTrans) what;
-        } catch (Exception x) {
+                return (session.equals(other.session)
-            return false;
+                        && path.equalsIgnoreCase(other.path)
+                        && values.equals(other.values)
+                        && ifModifiedSince == other.ifModifiedSince
+                        && etags.equals(other.etags));
+            }
         }
+        return false;
     }
 
     /**
@@ -284,11 +290,8 @@ public class RequestTrans implements Serializable {
      * @param etagHeader ...
      */
     public void setETags(String etagHeader) {
-        etags = new HashSet();
-
         if (etagHeader.indexOf(",") > -1) {
             StringTokenizer st = new StringTokenizer(etagHeader, ", \r\n");
-
             while (st.hasMoreTokens())
                 etags.add(st.nextToken());
         } else {

src/helma/framework/ResponseTrans.java

@@ -477,10 +477,11 @@ public final class ResponseTrans extends Writer implements Serializable {
      * @param appName the application name
      * @param message the error message
      */
-    public void writeErrorReport(String appName, String message) {
+    public void reportError(String appName, String message) {
         if (reqtrans.isXmlRpc()) {
             writeXmlRpcError(new RuntimeException(message));
         } else {
+            status = 500;
             write("<html><body><h3>");
             write("Error in application ");
             write(appName);
@@ -576,19 +577,22 @@ public final class ResponseTrans extends Writer implements Serializable {
             }
         }
 
-        // if etag is not set, calc MD5 digest and check it, but only if not a redirect
+        boolean autoETags = "true".equals(app.getProperty("autoETags", "true"));
-        if (etag == null && lastModified == -1 && redir == null) {
+        // if etag is not set, calc MD5 digest and check it, but only if
+        // not a redirect or error
+        if (autoETags &&
+                etag == null &&
+                lastModified == -1 &&
+                status == 200 &&
+                redir == null) {
             try {
                 digest = MessageDigest.getInstance("MD5");
-
                 // if (contentType != null)
                 //     digest.update (contentType.getBytes());
                 byte[] b = digest.digest(response);
-
                 etag = "\"" + new String(Base64.encode(b)) + "\"";
-
                 // only set response to 304 not modified if no cookies were set
-                if (reqtrans != null && reqtrans.hasETag(etag) && countCookies() == 0) {
+                if (reqtrans.hasETag(etag) && countCookies() == 0) {
                     response = new byte[0];
                     notModified = true;
                 }
@@ -671,13 +675,12 @@ public final class ResponseTrans extends Writer implements Serializable {
      * @param modified the Last-Modified header in milliseconds
      */
     public void setLastModified(long modified) {
-        if ((modified > -1) && (reqtrans != null) &&
+        // date headers don't do milliseconds, round to seconds
-                (reqtrans.getIfModifiedSince() >= modified)) {
+        lastModified = (modified / 1000) * 1000;
+        if (reqtrans.getIfModifiedSince() == lastModified) {
             notModified = true;
             throw new RedirectException(null);
         }
-
-        lastModified = modified;
     }
 
     /**
@@ -696,8 +699,7 @@ public final class ResponseTrans extends Writer implements Serializable {
      */
     public void setETag(String value) {
         etag = (value == null) ? null : ("\"" + value + "\"");
-
+        if (etag != null && reqtrans.hasETag(etag)) {
-        if ((etag != null) && (reqtrans != null) && reqtrans.hasETag(etag)) {
             notModified = true;
             throw new RedirectException(null);
         }

src/helma/framework/core/Application.java

@@ -674,7 +674,7 @@ public final class Application implements IPathElement, Runnable {
         } catch (Exception x) {
             errorCount += 1;
             res = new ResponseTrans(this, req);
-            res.writeErrorReport(name, x.getMessage());
+            res.reportError(name, x.getMessage());
         } finally {
             if (primaryRequest) {
                 activeRequests.remove(req);

src/helma/framework/core/RequestEvaluator.java

@@ -248,7 +248,6 @@ public final class RequestEvaluator implements Runnable {
                                             currentElement = root;
                                             requestPath.add(null, currentElement);
 
-
                                             for (int i = 0; i < ntokens; i++) {
                                                 if (currentElement == null) {
                                                     throw new FrameworkException("Object not found.");
@@ -496,7 +495,7 @@ public final class RequestEvaluator implements Runnable {
                                 Thread.sleep((long) (base + (Math.random() * base * 2)));
                             } catch (InterruptedException interrupt) {
                                 // we got interrrupted, create minimal error message 
-                                res.writeErrorReport(app.getName(), error);
+                                res.reportError(app.getName(), error);
                                 done = true;
                                 // and release resources and thread
                                 rtx = null;
@@ -508,7 +507,7 @@ public final class RequestEvaluator implements Runnable {
                                 error = "Application too busy, please try again later";
 
                             // error in error action. use traditional minimal error message
-                            res.writeErrorReport(app.getName(), error);
+                            res.reportError(app.getName(), error);
                             done = true;
                         }
                     } catch (Throwable x) {
@@ -557,7 +556,7 @@ public final class RequestEvaluator implements Runnable {
                             }
                         } else {
                             // error in error action. use traditional minimal error message
-                            res.writeErrorReport(app.getName(), error);
+                            res.reportError(app.getName(), error);
                             done = true;
                         }
                     }
@@ -695,7 +694,7 @@ public final class RequestEvaluator implements Runnable {
             app.logEvent("Stopping Thread for Request " + app.getName() + "/" + req.getPath());
             stopTransactor();
             res.reset();
-            res.writeErrorReport(app.getName(), "Request timed out");
+            res.reportError(app.getName(), "Request timed out");
         }
 
         session.commit(this);
@@ -894,7 +893,7 @@ public final class RequestEvaluator implements Runnable {
         this.reqtype = reqtype;
         req = new RequestTrans(reqtypeName, functionName);
         session = new Session(functionName, app);
-        res = new ResponseTrans(app, getRequest());
+        res = new ResponseTrans(app, req);
         result = null;
         exception = null;
     }

src/helma/servlet/AbstractServletClient.java

@@ -332,7 +332,7 @@ public abstract class AbstractServletClient extends HttpServlet {
             }
 
             // write response
-            writeResponse(request, response, restrans);
+            writeResponse(request, response, reqtrans, restrans);
         } catch (Exception x) {
             try {
                 if (debug) {
@@ -352,8 +352,9 @@ public abstract class AbstractServletClient extends HttpServlet {
         }
     }
 
-    void writeResponse(HttpServletRequest req, HttpServletResponse res,
+    protected void writeResponse(HttpServletRequest req, HttpServletResponse res,
-                       ResponseTrans hopres) throws IOException {
+                                 RequestTrans hopreq, ResponseTrans hopres)
+            throws IOException {
         if (hopres.getForward() != null) {
             sendForward(res, req, hopres);
             return;
@@ -389,9 +390,8 @@ public abstract class AbstractServletClient extends HttpServlet {
 
             // set last-modified header to now
             long modified = hopres.getLastModified();
-
             if (modified > -1) {
-                res.setDateHeader("Last-Modified", System.currentTimeMillis());
+                res.setDateHeader("Last-Modified", modified);
             }
 
             res.setContentLength(hopres.getContentLength());
@@ -498,7 +498,7 @@ public abstract class AbstractServletClient extends HttpServlet {
         long lastModified = (file.lastModified() / 1000) * 1000;
         long ifModifiedSince = req.getDateHeader("If-Modified-Since");
         if (lastModified == ifModifiedSince) {
-            res.setStatus(304);
+            res.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
             return;
         }
         int length = (int) file.length();