/// <summary>
/// Invokes a currently registered Velocimacro with the parms provided
/// and places the rendered stream into the writer.
/// <br>
/// Note : currently only accepts args to the VM if they are in the context.
/// </summary>
/// <param name="vmName">name of Velocimacro to call
/// </param>
/// <param name="logTag">string to be used for template name in case of error
/// </param>
/// <param name="params[]">args used to invoke Velocimacro. In context key format :
/// eg "foo","bar" (rather than "$foo","$bar")
/// </param>
/// <param name="context">Context object containing data/objects used for rendering.
/// </param>
/// <param name="writer"> Writer for output stream
/// </param>
/// <returns>true if Velocimacro exists and successfully invoked, false otherwise.
/// </returns>
public static bool InvokeVelocimacro(System.String vmName, System.String logTag, System.String[] params_Renamed, IContext context, TextWriter writer)
{
/*
* check parms
*/
if (vmName == null || params_Renamed == null || context == null || writer == null || logTag == null)
{
RuntimeSingleton.error("Velocity.invokeVelocimacro() : invalid parameter");
return(false);
}
/*
* does the VM exist?
*/
if (!RuntimeSingleton.isVelocimacro(vmName, logTag))
{
RuntimeSingleton.error("Velocity.invokeVelocimacro() : VM '" + vmName + "' not registered.");
return(false);
}
/*
* now just create the VM call, and use evaluate
*/
System.Text.StringBuilder construct = new System.Text.StringBuilder("#");
construct.Append(vmName);
construct.Append("(");
for (int i = 0; i < params_Renamed.Length; i++)
{
construct.Append(" $");
construct.Append(params_Renamed[i]);
}
construct.Append(" )");
try {
bool retval = Evaluate(context, writer, logTag, construct.ToString());
return(retval);
} catch (System.Exception e) {
RuntimeSingleton.error("Velocity.invokeVelocimacro() : error " + e);
}
return(false);
}
/// <summary>
/// merges a template and puts the rendered stream into the writer
/// </summary>
/// <param name="templateName">name of template to be used in merge
/// </param>
/// <param name="encoding">encoding used in template
/// </param>
/// <param name="context"> filled context to be used in merge
/// </param>
/// <param name="writer"> writer to write template into
/// </param>
/// <returns>true if successful, false otherwise. Errors
/// logged to velocity log
/// @since Velocity v1.1
/// </returns>
public static bool MergeTemplate(System.String templateName, System.String encoding, IContext context, TextWriter writer)
{
Template template = RuntimeSingleton.getTemplate(templateName, encoding)
;
if (template == null)
{
RuntimeSingleton.error("Velocity.parseTemplate() failed loading template '" + templateName + "'");
return(false);
}
else
{
template.Merge(context, writer);
return(true);
}
}
/// <summary>
/// Renders the input reader using the context into the output writer.
/// To be used when a template is dynamically constructed, or want to
/// use Velocity as a token replacer.
/// </summary>
/// <param name="context">context to use in rendering input string</param>
/// <param name="out"> Writer in which to render the output</param>
/// <param name="logTag"> string to be used as the template name for log messages in case of error</param>
/// <param name="reader">Reader containing the VTL to be rendered</param>
/// <returns>true if successful, false otherwise. If false, see Velocity runtime log</returns>
public static bool Evaluate(IContext context, TextWriter writer, System.String logTag, TextReader reader)
{
SimpleNode nodeTree = null;
try {
nodeTree = RuntimeSingleton.parse(reader, logTag);
} catch (ParseException pex) {
throw new ParseErrorException(pex.Message);
}
/*
* now we want to init and render
*/
if (nodeTree != null)
{
InternalContextAdapterImpl ica = new InternalContextAdapterImpl(context);
ica.PushCurrentTemplateName(logTag);
try {
try {
nodeTree.init(ica, RuntimeSingleton.RuntimeServices);
} catch (System.Exception e) {
RuntimeSingleton.error("Velocity.evaluate() : init exception for tag = " + logTag + " : " + e);
}
/*
* now render, and let any exceptions fly
*/
nodeTree.render(ica, writer);
} finally {
ica.PopCurrentTemplateName();
}
return(true);
}
return(false);
}
/// <summary>
/// Log an error message.
/// </summary>
/// <param name="Object">message to log</param>
public static void Error(System.Object message)
{
RuntimeSingleton.error(message);
}
