xmlhierarchyconfigurator.cs

网上书店系统

			// Create a new log4net.Logger object from the <logger> element.
			string loggerName = loggerElement.GetAttribute(NAME_ATTR);

			LogLog.Debug("XmlHierarchyConfigurator: Retrieving an instance of log4net.Repository.Logger for logger [" + loggerName + "].");
			Logger log = m_hierarchy.GetLogger(loggerName) as Logger;

			// Setting up a logger needs to be an atomic operation, in order
			// to protect potential log operations while logger
			// configuration is in progress.
			lock(log) 
			{
				bool additivity = OptionConverter.ToBoolean(loggerElement.GetAttribute(ADDITIVITY_ATTR), true);
	
				LogLog.Debug("XmlHierarchyConfigurator: Setting [" + log.Name + "] additivity to [" + additivity + "].");
				log.Additivity = additivity;
				ParseChildrenOfLoggerElement(loggerElement, log, false);
			}
		}

		/// <summary>
		/// Parses the root logger element.
		/// </summary>
		/// <param name="rootElement">The root element.</param>
		/// <remarks>
		/// <para>
		/// Parse an XML element that represents the root logger.
		/// </para>
		/// </remarks>
		protected void ParseRoot(XmlElement rootElement) 
		{
			Logger root = m_hierarchy.Root;
			// logger configuration needs to be atomic
			lock(root) 
			{	
				ParseChildrenOfLoggerElement(rootElement, root, true);
			}
		}

		/// <summary>
		/// Parses the children of a logger element.
		/// </summary>
		/// <param name="catElement">The category element.</param>
		/// <param name="log">The logger instance.</param>
		/// <param name="isRoot">Flag to indicate if the logger is the root logger.</param>
		/// <remarks>
		/// <para>
		/// Parse the child elements of a &lt;logger&gt; element.
		/// </para>
		/// </remarks>
		protected void ParseChildrenOfLoggerElement(XmlElement catElement, Logger log, bool isRoot) 
		{
			// Remove all existing appenders from log. They will be
			// reconstructed if need be.
			log.RemoveAllAppenders();

			foreach (XmlNode currentNode in catElement.ChildNodes)
			{
				if (currentNode.NodeType == XmlNodeType.Element) 
				{
					XmlElement currentElement = (XmlElement) currentNode;
	
					if (currentElement.LocalName == APPENDER_REF_TAG)
					{
						IAppender appender = FindAppenderByReference(currentElement);
						string refName =  currentElement.GetAttribute(REF_ATTR);
						if (appender != null)
						{
							LogLog.Debug("XmlHierarchyConfigurator: Adding appender named [" + refName + "] to logger [" + log.Name + "].");
							log.AddAppender(appender);
						}
						else 
						{
							LogLog.Error("XmlHierarchyConfigurator: Appender named [" + refName + "] not found.");
						}
					} 
					else if (currentElement.LocalName == LEVEL_TAG || currentElement.LocalName == PRIORITY_TAG) 
					{
						ParseLevel(currentElement, log, isRoot);	
					} 
					else
					{
						SetParameter(currentElement, log);
					}
				}
			}

			IOptionHandler optionHandler = log as IOptionHandler;
			if (optionHandler != null) 
			{
				optionHandler.ActivateOptions();
			}
		}

		/// <summary>
		/// Parses an object renderer.
		/// </summary>
		/// <param name="element">The renderer element.</param>
		/// <remarks>
		/// <para>
		/// Parse an XML element that represents a renderer.
		/// </para>
		/// </remarks>
		protected void ParseRenderer(XmlElement element) 
		{
			string renderingClassName = element.GetAttribute(RENDERING_TYPE_ATTR);
			string renderedClassName = element.GetAttribute(RENDERED_TYPE_ATTR);

			LogLog.Debug("XmlHierarchyConfigurator: Rendering class [" + renderingClassName + "], Rendered class [" + renderedClassName + "].");
			IObjectRenderer renderer = (IObjectRenderer)OptionConverter.InstantiateByClassName(renderingClassName, typeof(IObjectRenderer), null);
			if (renderer == null) 
			{
				LogLog.Error("XmlHierarchyConfigurator: Could not instantiate renderer [" + renderingClassName + "].");
				return;
			} 
			else 
			{
				try 
				{
					m_hierarchy.RendererMap.Put(SystemInfo.GetTypeFromString(renderedClassName, true, true), renderer);
				} 
				catch(Exception e) 
				{
					LogLog.Error("XmlHierarchyConfigurator: Could not find class [" + renderedClassName + "].", e);
				}
			}
		}

		/// <summary>
		/// Parses a level element.
		/// </summary>
		/// <param name="element">The level element.</param>
		/// <param name="log">The logger object to set the level on.</param>
		/// <param name="isRoot">Flag to indicate if the logger is the root logger.</param>
		/// <remarks>
		/// <para>
		/// Parse an XML element that represents a level.
		/// </para>
		/// </remarks>
		protected void ParseLevel(XmlElement element, Logger log, bool isRoot) 
		{
			string loggerName = log.Name;
			if (isRoot) 
			{
				loggerName = "root";
			}

			string levelStr = element.GetAttribute(VALUE_ATTR);
			LogLog.Debug("XmlHierarchyConfigurator: Logger [" + loggerName + "] Level string is [" + levelStr + "].");
	
			if (INHERITED == levelStr) 
			{
				if (isRoot) 
				{
					LogLog.Error("XmlHierarchyConfigurator: Root level cannot be inherited. Ignoring directive.");
				} 
				else 
				{
					LogLog.Debug("XmlHierarchyConfigurator: Logger [" + loggerName + "] level set to inherit from parent.");	
					log.Level = null;
				}
			} 
			else 
			{
				log.Level = log.Hierarchy.LevelMap[levelStr];
				if (log.Level == null)
				{
					LogLog.Error("XmlHierarchyConfigurator: Undefined level [" + levelStr + "] on Logger [" + loggerName + "].");
				}
				else
				{
					LogLog.Debug("XmlHierarchyConfigurator: Logger [" + loggerName + "] level set to [name=\"" + log.Level.Name + "\",value=" + log.Level.Value + "].");	
				}
			}
		}

		/// <summary>
		/// Sets a parameter on an object.
		/// </summary>
		/// <param name="element">The parameter element.</param>
		/// <param name="target">The object to set the parameter on.</param>
		/// <remarks>
		/// The parameter name must correspond to a writable property
		/// on the object. The value of the parameter is a string,
		/// therefore this function will attempt to set a string
		/// property first. If unable to set a string property it
		/// will inspect the property and its argument type. It will
		/// attempt to call a static method called <c>Parse</c> on the
		/// type of the property. This method will take a single
		/// string argument and return a value that can be used to
		/// set the property.
		/// </remarks>
		protected void SetParameter(XmlElement element, object target) 
		{
			// Get the property name
			string name = element.GetAttribute(NAME_ATTR);

			// If the name attribute does not exist then use the name of the element
			if (element.LocalName != PARAM_TAG || name == null || name.Length == 0)
			{
				name = element.LocalName;
			}

			// Look for the property on the target object
			Type targetType = target.GetType();
			Type propertyType = null;

			PropertyInfo propInfo = null;
			MethodInfo methInfo = null;

			// Try to find a writable property
			propInfo = targetType.GetProperty(name, BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.IgnoreCase);
			if (propInfo != null && propInfo.CanWrite)
			{
				// found a property
				propertyType = propInfo.PropertyType;
			}
			else
			{
				propInfo = null;

				// look for a method with the signature Add<property>(type)
				methInfo = FindMethodInfo(targetType, name);

				if (methInfo != null)
				{
					propertyType = methInfo.GetParameters()[0].ParameterType;
				}
			}

			if (propertyType == null)
			{
				LogLog.Error("XmlHierarchyConfigurator: Cannot find Property [" + name + "] to set object on [" + target.ToString() + "]");
			}
			else
			{
				string propertyValue = null;

				if (element.GetAttributeNode(VALUE_ATTR) != null)
				{
					propertyValue = element.GetAttribute(VALUE_ATTR);
				}
				else if (element.HasChildNodes)
				{
					// Concatenate the CDATA and Text nodes together
					foreach(XmlNode childNode in element.ChildNodes)
					{
						if (childNode.NodeType == XmlNodeType.CDATA || childNode.NodeType == XmlNodeType.Text)
						{
							if (propertyValue == null)
							{
								propertyValue = childNode.InnerText;
							}
							else
							{
								propertyValue += childNode.InnerText;
							}
						}
					}
				}

				if(propertyValue != null)
				{
#if !NETCF	
					try
					{
						// Expand environment variables in the string.
						propertyValue = OptionConverter.SubstituteVariables(propertyValue, Environment.GetEnvironmentVariables());
					}
					catch(System.Security.SecurityException)
					{
						// This security exception will occur if the caller does not have 
						// unrestricted environment permission. If this occurs the expansion 
						// will be skipped with the following warning message.
						LogLog.Debug("XmlHierarchyConfigurator: Security exception while trying to expand environment variables. Error Ignored. No Expansion.");
					}
#endif

					Type parsedObjectConversionTargetType = null;

					// Check if a specific subtype is specified on the element using the 'type' attribute
					string subTypeString = element.GetAttribute(TYPE_ATTR);
					if (subTypeString != null && subTypeString.Length > 0)
					{
						// Read the explicit subtype
						try
						{
							Type subType = SystemInfo.GetTypeFromString(subTypeString, true, true);

							LogLog.Debug("XmlHierarchyConfigurator: Parameter ["+name+"] specified subtype ["+subType.FullName+"]");

							if (!propertyType.IsAssignableFrom(subType))
							{
								// Check if there is an appropriate type converter
								if (OptionConverter.CanConvertTypeTo(subType, propertyType))
								{
									// Must re-convert to the real property type
									parsedObjectConversionTargetType = propertyType;

									// Use sub type as intermediary type
									propertyType = subType;
								}
								else
								{
									LogLog.Error("XmlHierarchyConfigurator: Subtype ["+subType.FullName+"] set on ["+name+"] is not a subclass of property type ["+propertyType.FullName+"] and there are no acceptable type conversions.");
								}
							}
							else
							{
								// The subtype specified is found and is actually a subtype of the property
								// type, therefore we can switch to using this type.
								propertyType = subType;
							}
						}
						catch(Exception ex)
						{
							LogLog.Error("XmlHierarchyConfigurator: Failed to find type ["+subTypeString+"] set on ["+name+"]", ex);
						}
					}

					// Now try to convert the string value to an acceptable type
					// to pass to this property.

					object convertedValue = ConvertStringTo(propertyType, propertyValue);
					
					// Check if we need to do an additional conversion
					if (convertedValue != null && parsedObjectConversionTargetType != null)
					{
						LogLog.Debug("XmlHierarchyConfigurator: Performing additional conversion of value from [" + convertedValue.GetType().Name + "] to [" + parsedObjectConversionTargetType.Name + "]");
						convertedValue = OptionConverter.ConvertTypeTo(convertedValue, parsedObjectConversionTargetType);
					}

					if (convertedValue != null)
					{
						if (propInfo != null)
						{
							// Got a converted result
							LogLog.Debug("XmlHierarchyConfigurator: Setting Property [" + propInfo.Name + "] to " + convertedValue.GetType().Name + " value [" + convertedValue.ToString() + "]");

							try
							{
								// Pass to the property
								propInfo.SetValue(target, convertedValue, BindingFlags.SetProperty, null, null, CultureInfo.InvariantCulture);
							}
							catch(TargetInvocationException targetInvocationEx)
							{
								LogLog.Error("XmlHierarchyConfigurator: Failed to set parameter [" + propInfo.Name + "] on object [" + target + "] using value [" + convertedValue + "]", targetInvocationEx.InnerException);
							}
						}
						else if (methInfo != null)
						{
							// Got a converted result
							LogLog.Debug("XmlHierarchyConfigurator: Setting Collection Property [" + methInfo.Name + "] to " + convertedValue.GetType().Name + " value [" + convertedValue.ToString() + "]");