Caf::Pdm: Added better Error messages and Recovery when encountering unknown field names and class types

p4#: 21001

cafProjectDataModel/cafPdmField.inl

@@ -19,6 +19,7 @@
 
 #include "cafPdmObject.h"
 #include <vector>
+#include <iostream>
 #include "cafPdmUiFieldEditorHandle.h"
 
 namespace caf
@@ -226,26 +227,66 @@ template<typename DataType >
 void caf::PdmField<DataType*>::readFieldData(QXmlStreamReader& xmlStream)
 {
     PdmFieldIOHelper::skipCharactersAndComments(xmlStream);
-    if (!xmlStream.isStartElement()) return; // Todo: Error handling
-
-    QString className = xmlStream.name().toString();
-
-    if (m_fieldValue.isNull())
+    if (!xmlStream.isStartElement())
     {
-        m_fieldValue.setRawPtr(caf::PdmObjectFactory::instance()->create(className));
-        if (m_fieldValue.notNull())
-        {
-            m_fieldValue.rawPtr()->addParentField(this);
-        }
+        return; // This happens when the field is "shortcut" empty (written like: <ElementName/>) 
     }
 
-    if (m_fieldValue.isNull()) return; // Warning: Unknown className read
+    QString className = xmlStream.name().toString();
+    PdmObject* obj = NULL;
 
-    if (xmlStream.name() != m_fieldValue.rawPtr()->classKeyword()) return; // Error: Field contains different class type than on file
+    // Create an object if needed 
+    if (m_fieldValue.isNull())
+    {
+        obj = caf::PdmObjectFactory::instance()->create(className);
 
-    m_fieldValue.rawPtr()->readFields(xmlStream);
+        if (obj == NULL)
+        {
+            std::cout << "Line " << xmlStream.lineNumber() << ": Warning: Unknown object type with class name: " << className.toLatin1().data() << " found while reading the field : " << this->keyword().toLatin1().data() << std::endl;
+
+            xmlStream.skipCurrentElement(); // Skip to the endelement of the object we was supposed to read
+            xmlStream.skipCurrentElement(); // Skip to the endelement of this field
+            return;
+        }
+        else
+        {
+            if (dynamic_cast<DataType *>(obj) == NULL)
+            {
+                assert(false); // Inconsistency in the factory. It creates objects of wrong type from the ClassKeyword
+
+                xmlStream.skipCurrentElement(); // Skip to the endelement of the object we was supposed to read
+                xmlStream.skipCurrentElement(); // Skip to the endelement of this field
+
+                return;
+            }
+
+            m_fieldValue.setRawPtr(obj);
+            obj->addParentField(this);
+        }
+    }
+    else
+    {
+        obj = m_fieldValue.rawPtr();
+    }
+
+    if (className != obj->classKeyword())
+    {
+        // Error: Field contains different class type than on file
+        std::cout << "Line " << xmlStream.lineNumber() << ": Warning: Unknown object type with class name: " << className.toLatin1().data() << " found while reading the field : " << this->keyword().toLatin1().data() << std::endl;
+        std::cout << "                     Expected class name: " << obj->classKeyword().toLatin1().data() << std::endl;
+
+        xmlStream.skipCurrentElement(); // Skip to the endelement of the object we was supposed to read
+        xmlStream.skipCurrentElement(); // Skip to the endelement of this field
+
+        return; 
+    }
+
+    // Everything seems ok, so read the contents of the object:
+
+    obj->readFields(xmlStream);
+    
+    // Make stream point to endElement of this field
 
-    // Make stream point to end of element
     QXmlStreamReader::TokenType type;
     type = xmlStream.readNext();
     PdmFieldIOHelper::skipCharactersAndComments(xmlStream);
@@ -540,8 +581,17 @@ template<typename DataType>
         {
             // Warning: Unknown className read
             // Skip to corresponding end element
-            xmlStream.skipCurrentElement();
+
+            std::cout << "Line " << xmlStream.lineNumber() << ": Warning: Unknown object type with class name: " << className.toLatin1().data() << " found while reading the field : " << this->keyword().toLatin1().data() << std::endl;
+
+            // Skip to EndElement of the object
+            xmlStream.skipCurrentElement(); 
+
+            // Jump off the end element, and head for next start element (or the final EndElement of the field)
+            QXmlStreamReader::TokenType type;
+            type = xmlStream.readNext();
             PdmFieldIOHelper::skipCharactersAndComments(xmlStream);
+
             continue; 
         }
 
@@ -549,18 +599,24 @@ template<typename DataType>
 
         if (currentObject == NULL)
         {
-            // Warning: Inconsistency in factory !! Assert ?
-            // Skip to corresponding end element
+            assert(false); // There is an inconsistency in the factory. It creates objects of type not matching the ClassKeyword
+
+            // Skip to EndElement of the object
             xmlStream.skipCurrentElement();
+
+            // Jump off the end element, and head for next start element (or the final EndElement of the field)
+            QXmlStreamReader::TokenType type;
+            type = xmlStream.readNext();
             PdmFieldIOHelper::skipCharactersAndComments(xmlStream);
+
             continue; 
         }
 
         currentObject->readFields(xmlStream);
         this->push_back(currentObject);
 
-        // Skip comments and for some reason: Characters. The last bit should not be correct, 
-        // but Qt reports a character token between EndElement and StartElement
+        // Jump off the end element, and head for next start element (or the final EndElement of the field)
+        // Qt reports a character token between EndElements and StartElements so skip it
 
         QXmlStreamReader::TokenType type;
         type = xmlStream.readNext();

cafProjectDataModel/cafPdmObject.cpp

@@ -30,10 +30,10 @@ namespace caf
 
 //--------------------------------------------------------------------------------------------------
 /// Reads all the fields into this PdmObject
-/// Assumes xmlStream points to the start element token of the containing object.
+/// Assumes xmlStream points to the start element token of the PdmObject for which to read fields.
 /// ( and not first token of object content)
 /// This makes attribute based field storage possible.
-/// Leaves the xmlStream pointing to the EndElement corresponding to the start element.
+/// Leaves the xmlStream pointing to the EndElement of the PdmObject.
 //--------------------------------------------------------------------------------------------------
 void PdmObject::readFields (QXmlStreamReader& xmlStream )
 {
@@ -48,6 +48,11 @@ void PdmObject::readFields (QXmlStreamReader& xmlStream )
        case QXmlStreamReader::StartElement:
            {
                QString name = xmlStream.name().toString();
+               if (name == QString("SimpleObjPtrField"))
+               {
+                   int a;
+                   a = 2 + 7;
+               }
                PdmFieldHandle* currentField = findField(name);
                if (currentField)
                {
@@ -76,6 +81,7 @@ void PdmObject::readFields (QXmlStreamReader& xmlStream )
        case QXmlStreamReader::EndElement:
            {
                // End of object.
+               QString name = xmlStream.name().toString(); // For debugging
                isObjectFinished = true;
            }
            break;