I ported this code into the next Mango release with a couple of minor changes.

1. The message properties key for the new logging type is "pointEdit.logging.type.tsChange".
2. The ScriptExecutor methods now return a PointValueTime object, rather than an Object. The two methods with similar signatures have been combined.

This part of reading data tables is working fine. controlling the row pointer with point detectors and event handlers works OK but eventually gets hung up after some kind of exception.

=== modified file 'src/com/serotonin/mango/rt/dataImage/DataPointRT.java'
--- src/com/serotonin/mango/rt/dataImage/DataPointRT.java       2009-10-20 21:08:00 +0000
+++ src/com/serotonin/mango/rt/dataImage/DataPointRT.java       2009-10-21 03:04:37 +0000
@@ -200,6 +200,17 @@
         case DataPointVO.LoggingTypes.ALL :
             logValue = true;
             break;
+        case DataPointVO.LoggingTypes.ON_TS_CHANGE :
+               if (pointValue == null) 
+                       logValue = true;
+               else {
+                       if (newValue.getTime() != pointValue.getTime())
+                               logValue = true;
+                       else
+                               logValue = false;
+               }
+               saveValue = logValue;
+               break;
         case DataPointVO.LoggingTypes.INTERVAL :
             intervalSave(newValue);
         default :

=== modified file 'src/com/serotonin/mango/rt/dataSource/meta/MetaPointLocatorRT.java'
--- src/com/serotonin/mango/rt/dataSource/meta/MetaPointLocatorRT.java  2009-10-20 21:08:00 +0000
+++ src/com/serotonin/mango/rt/dataSource/meta/MetaPointLocatorRT.java  2009-10-21 03:04:37 +0000
@@ -237,7 +237,10 @@
                 if (result == null)
                     dataSource.raiseScriptError(runtime, dataPoint, new LocalizableMessage("event.meta.nullResult"));
                 else
-                    dataPoint.updatePointValue(new PointValueTime(result, runtime));
+                       if (result instanceof PointValueTime)
+                               dataPoint.updatePointValue((PointValueTime)result);
+                       else 
+                               dataPoint.updatePointValue(new PointValueTime(result, runtime));
             }
             catch (ScriptException e) {
                 dataSource.raiseScriptError(runtime, dataPoint, new LocalizableMessage("common.default",

=== modified file 'src/com/serotonin/mango/rt/dataSource/meta/ScriptExecutor.java'
--- src/com/serotonin/mango/rt/dataSource/meta/ScriptExecutor.java      2009-10-20 21:08:00 +0000
+++ src/com/serotonin/mango/rt/dataSource/meta/ScriptExecutor.java      2009-10-21 03:04:37 +0000
@@ -38,6 +38,7 @@
 import com.serotonin.mango.rt.RuntimeManager;
 import com.serotonin.mango.rt.dataImage.DataPointRT;
 import com.serotonin.mango.rt.dataImage.IDataPoint;
+import com.serotonin.mango.rt.dataImage.PointValueTime;
 import com.serotonin.web.i18n.LocalizableMessage;
 
 /**
@@ -84,6 +85,25 @@
             return null;
         }
         
+        // i've changed things so we may have a pointvalue time with
+        // an obj and a ts. need to return a PVT here with obj cast correctly.
+        if (result instanceof PointValueTime) {
+        	PointValueTime pvt = (PointValueTime)result;
+        	Object value = pvt.getValue();
+        	long timestamp = pvt.getTime();
+        	
+            // See if the type matches.
+            if (dataTypeId == DataTypes.BINARY && value instanceof Boolean)
+                return new PointValueTime(value, timestamp);
+            if (dataTypeId == DataTypes.MULTISTATE && value instanceof Number)
+                return new PointValueTime(((Number)value).intValue(), timestamp);
+            if (dataTypeId == DataTypes.NUMERIC && value instanceof Number)
+                return new PointValueTime(((Number)value).doubleValue(), timestamp);
+            if (dataTypeId == DataTypes.ALPHANUMERIC && value instanceof String)
+                return new PointValueTime(value, timestamp);
+        }
+        
+        
         // See if the type matches.
         if (dataTypeId == DataTypes.BINARY && result instanceof Boolean)
             return result;
@@ -120,6 +140,9 @@
         engine.put("MONTH", Common.TimePeriods.MONTHS);
         engine.put("YEAR", Common.TimePeriods.YEARS);
         
+        // a variable to put the script-generated timestamp in.
+        engine.put("TIMESTAMP", null);
+        
         // Put the context variables into the engine with engine scope.
         for (String varName : context.keySet()) {
             IDataPoint point = context.get(varName);
@@ -151,6 +174,11 @@
         if (result instanceof AbstractPointWrapper)
             result = ((AbstractPointWrapper)result).getValueImpl();
         
+        Object ts = engine.get("TIMESTAMP");
+        if (ts != null && ts instanceof Number) {
+        	return new PointValueTime(result, ((Number)ts).longValue() );
+        }
+        
         return result;
     }
     

=== modified file 'src/com/serotonin/mango/vo/DataPointVO.java'
--- src/com/serotonin/mango/vo/DataPointVO.java	2009-10-20 21:08:00 +0000
+++ src/com/serotonin/mango/vo/DataPointVO.java	2009-10-21 03:04:37 +0000
@@ -64,6 +64,7 @@
         int ALL = 2;
         int NONE = 3;
         int INTERVAL = 4;
+        int ON_TS_CHANGE = 10;
     }
     private static final ExportCodes LOGGING_TYPE_CODES = new ExportCodes();
     static {
@@ -71,6 +72,7 @@
         LOGGING_TYPE_CODES.addElement(LoggingTypes.ALL, "ALL", "pointEdit.logging.type.all");
         LOGGING_TYPE_CODES.addElement(LoggingTypes.NONE, "NONE", "pointEdit.logging.type.never");
         LOGGING_TYPE_CODES.addElement(LoggingTypes.INTERVAL, "INTERVAL", "pointEdit.logging.type.interval");
+        LOGGING_TYPE_CODES.addElement(LoggingTypes.ON_TS_CHANGE, "TIMESTAMP", "pointEdit.logging.type.timestamp");
     }
     
     public interface PurgeTypes {

=== modified file 'src/com/serotonin/mango/web/mvc/controller/DataPointEditController.java'
--- src/com/serotonin/mango/web/mvc/controller/DataPointEditController.java	2009-10-20 21:08:00 +0000
+++ src/com/serotonin/mango/web/mvc/controller/DataPointEditController.java	2009-10-21 03:04:37 +0000
@@ -128,7 +128,8 @@
         if (point.getLoggingType() != DataPointVO.LoggingTypes.ON_CHANGE && 
                 point.getLoggingType() != DataPointVO.LoggingTypes.ALL &&
                 point.getLoggingType() != DataPointVO.LoggingTypes.NONE &&
-                point.getLoggingType() != DataPointVO.LoggingTypes.INTERVAL)
+                point.getLoggingType() != DataPointVO.LoggingTypes.INTERVAL &&
+                point.getLoggingType() != DataPointVO.LoggingTypes.ON_TS_CHANGE)
             ValidationUtils.rejectValue(errors, "loggingType", "validate.required");
         
         if (point.getLoggingType() == DataPointVO.LoggingTypes.INTERVAL) {

=== modified file 'war/WEB-INF/classes/messages_en.properties'
--- war/WEB-INF/classes/messages_en.properties	2009-10-20 21:08:00 +0000
+++ war/WEB-INF/classes/messages_en.properties	2009-10-21 03:04:37 +0000
@@ -1144,6 +1144,7 @@
 pointEdit.logging.type.all=All data
 pointEdit.logging.type.never=Do not log
 pointEdit.logging.type.interval=Interval
+pointEdit.logging.type.ts_change=When point timestamp changes
 pointEdit.logging.period=Interval logging period
 pointEdit.logging.every=Every
 pointEdit.logging.valueType=Value type

=== modified file 'war/WEB-INF/jsp/pointEdit/loggingProperties.jsp'
--- war/WEB-INF/jsp/pointEdit/loggingProperties.jsp	2009-10-20 21:08:00 +0000
+++ war/WEB-INF/jsp/pointEdit/loggingProperties.jsp	2009-10-21 03:04:37 +0000
@@ -33,7 +33,8 @@
       else
           tolerance.disabled = true;
       
-      if (loggingType == <%= DataPointVO.LoggingTypes.NONE %>) {
+      if (loggingType == <%= DataPointVO.LoggingTypes.NONE %> || 
+          loggingType == <%= DataPointVO.LoggingTypes.ON_TS_CHANGE %> ) {
           purgePeriod.disabled = true;
           purgeType.disabled = true;
       }
@@ -75,6 +76,7 @@
             <sst:option value="<%= Integer.toString(DataPointVO.LoggingTypes.ALL) %>"><fmt:message key="pointEdit.logging.type.all"/></sst:option>
             <sst:option value="<%= Integer.toString(DataPointVO.LoggingTypes.NONE) %>"><fmt:message key="pointEdit.logging.type.never"/></sst:option>
             <sst:option value="<%= Integer.toString(DataPointVO.LoggingTypes.INTERVAL) %>"><fmt:message key="pointEdit.logging.type.interval"/></sst:option>
+            <sst:option value="<%= Integer.toString(DataPointVO.LoggingTypes.ON_TS_CHANGE) %>"><fmt:message key="pointEdit.logging.type.ts_change"/></sst:option>
           </sst:select>
         </td>
         <td class="formError">${status.errorMessage}</td>

I've added typical date related functions including things like this:

p.time --&gt returns the timestamp of the value in milliseconds since the epoch

I've got a patch that allows the timestamp of a meta point to be set. This is useful when data is being read from a table and some point values are the date & time for the rest of the data in the row.

This was missing, but is added now and in for the next release. I've added typical date related functions including things like this:

p.time --&gt returns the timestamp of the value in milliseconds since the epoch
p.millis --&gt 0-999 the millisecond portion of p.time
p.second --&gt 0-60
p.minute --&gt 0-60
p.hour --&gt 0-23
p.day --&gt 1-28,31
p.dayOfWeek --&gt 1-7 where 1 is Sunday
p.dayOfYear --&gt 1-365,366
p.month --&gt 1-12
p.year --&gt four digits

Regards,
Petteri