Beispiel #1
0
        /// <summary>
        /// Return the xPath corresponding to the given property. The PropertyName String
        /// may be simple, nested, indexed or mapped.
        /// </summary>
        /// <param name="propertyName">is the event property name</param>
        /// <param name="namespace">is the default namespace</param>
        /// <param name="schemaModel">is the schema model</param>
        /// <param name="xPathContext">is the xpath factory instance to use</param>
        /// <param name="rootElementName">is the name of the root element</param>
        /// <param name="eventAdapterService">for type lookup and creation</param>
        /// <param name="xmlEventType">the resolving type</param>
        /// <param name="isAllowFragment">whether fragmenting is allowed</param>
        /// <param name="defaultNamespace">default namespace</param>
        /// <returns>
        /// xpath expression
        /// </returns>
        /// <throws>EPException is there are XPath errors</throws>
        public static EventPropertyGetter GetXPathResolution(String propertyName,
                                                             XPathNamespaceContext xPathContext,
                                                             String rootElementName,
                                                             String @namespace,
                                                             SchemaModel schemaModel,
                                                             EventAdapterService eventAdapterService,
                                                             BaseXMLEventType xmlEventType,
                                                             bool isAllowFragment,
                                                             String defaultNamespace)
        {
            if (Log.IsDebugEnabled)
            {
                Log.Debug("Determining XPath expression for property '" + propertyName + "'");
            }

            var ctx        = new XPathNamespaceContext();
            var namespaces = schemaModel.Namespaces;

            string defaultNamespacePrefix = null;

            for (int i = 0; i < namespaces.Count; i++)
            {
                var namespacePrefix = "n" + i;
                ctx.AddNamespace(namespacePrefix, namespaces[i]);
                if ((defaultNamespace != null) && (defaultNamespace == namespaces[i]))
                {
                    defaultNamespacePrefix = namespacePrefix;
                }
            }

            Property property  = PropertyParser.ParseAndWalk(propertyName);
            var      isDynamic = property.IsDynamic;

            var    rootComplexElement = SchemaUtil.FindRootElement(schemaModel, @namespace, rootElementName);
            string prefix             = ctx.LookupPrefix(rootComplexElement.Namespace);

            if (prefix == null)
            {
                prefix = "";
            }
            else
            {
                prefix += ':';
            }

            var xPathBuf = new StringBuilder();

            xPathBuf.Append('/');
            xPathBuf.Append(prefix);
            if (rootElementName.StartsWith("//"))
            {
                xPathBuf.Append(rootElementName.Substring(2));
            }
            else
            {
                xPathBuf.Append(rootElementName);
            }

            var parentComplexElement            = rootComplexElement;
            Pair <String, XPathResultType> pair = null;

            if (!(property is NestedProperty))
            {
                pair = MakeProperty(rootComplexElement, property, ctx, true, isDynamic, defaultNamespacePrefix);
                if (pair == null)
                {
                    throw new PropertyAccessException("Failed to locate property '" + propertyName + "' in schema");
                }
                xPathBuf.Append(pair.First);
            }
            else
            {
                NestedProperty nestedProperty = (NestedProperty)property;
                int            indexLast      = nestedProperty.Properties.Count - 1;

                for (int i = 0; i < indexLast + 1; i++)
                {
                    var isLast         = i == indexLast;
                    var propertyNested = nestedProperty.Properties[i];
                    pair = MakeProperty(parentComplexElement, propertyNested, ctx, isLast, isDynamic, defaultNamespacePrefix);
                    if (pair == null)
                    {
                        throw new PropertyAccessException("Failed to locate property '" + propertyName + "' nested property part '" + property.PropertyNameAtomic + "' in schema");
                    }

                    var text = propertyNested.PropertyNameAtomic;
                    var obj  = SchemaUtil.FindPropertyMapping(parentComplexElement, text);
                    if (obj is SchemaElementComplex)
                    {
                        parentComplexElement = (SchemaElementComplex)obj;
                    }
                    xPathBuf.Append(pair.First);
                }
            }

            var xPath = xPathBuf.ToString();

            if ((ExecutionPathDebugLog.IsEnabled) && (Log.IsDebugEnabled))
            {
                Log.Debug(".parse XPath for property '" + propertyName + "' is expression=" + xPath);
            }

            // Compile assembled XPath expression
            if (Log.IsDebugEnabled)
            {
                Log.Debug("Compiling XPath expression '" + xPath + "' for property '" + propertyName + "' using namespace context :" + ctx);
            }

            XPathExpression expr;

            try
            {
                expr = XPathExpression.Compile(xPath, ctx);
            }
            catch (XPathException e) {
                String detail = "Error constructing XPath expression from property expression '" + propertyName + "' expression '" + xPath + "'";
                if (e.Message != null)
                {
                    throw new EPException(detail + " :" + e.Message, e);
                }
                throw new EPException(detail, e);
            }

            // get type
            var item = property.GetPropertyTypeSchema(rootComplexElement, eventAdapterService);

            if ((item == null) && (!isDynamic))
            {
                return(null);
            }

            var resultType = isDynamic ? typeof(XmlNode) : SchemaUtil.ToReturnType(item);

            FragmentFactory fragmentFactory = null;

            if (isAllowFragment)
            {
                fragmentFactory = new FragmentFactoryDOMGetter(eventAdapterService, xmlEventType, propertyName);
            }

            return(new XPathPropertyGetter(propertyName, xPath, expr, pair.Second, resultType, fragmentFactory));
        }
Beispiel #2
0
 /// <summary>
 /// Ctor.
 /// </summary>
 /// <param name="eventAdapterService">for event type lookup</param>
 /// <param name="xmlEventType">the originating type</param>
 /// <param name="propertyExpression">property expression</param>
 public FragmentFactoryDOMGetter(EventAdapterService eventAdapterService, BaseXMLEventType xmlEventType, String propertyExpression)
 {
     _eventAdapterService = eventAdapterService;
     _xmlEventType        = xmlEventType;
     _propertyExpression  = propertyExpression;
 }