/// <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, 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 (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);
}
internal bool Render(DvslNode node, IContext context, TextWriter writer)
{
/*
* find if we have an AST where the xpath expression mathes
* for this node
*/
XmlNode dom4jnode = (XmlNode)node.NodeImpl;
XPathNavigator nav = dom4jnode.CreateNavigator();
SimpleNode sn = null;
for (int i = 0; i < xpathList.Count; i++)
{
Hashtable m = (Hashtable)xpathList[i];
XPathExpression expr = nav.Compile((String)m["xpath"]);
if (nav.Matches((String)m["xpath"]))
{
sn = (SimpleNode)m["ast"];
break;
}
}
// if we found something, render
if (sn != null)
{
InternalContextAdapterImpl ica = new InternalContextAdapterImpl(context);
ica.PushCurrentTemplateName(node.Name);
try
{
sn.render(ica, writer);
}
finally
{
ica.PopCurrentTemplateName();
}
return(true);
}
return(false);
}
/// <summary> Return name of this Velocimacro.
/// </summary>
/// <summary> Velocimacros are always LINE
/// type directives.
/// </summary>
/// <summary> sets the directive name of this VM
/// </summary>
/// <summary> sets the array of arguments specified in the macro definition
/// </summary>
/// <summary> returns the number of ars needed for this VM
/// </summary>
/// <summary> Sets the orignal macro body. This is simply the cat of the macroArray, but the
/// Macro object creates this once during parsing, and everyone shares it.
/// Note : it must not be modified.
/// </summary>
/// <summary> Renders the macro using the context
/// </summary>
public override bool render(InternalContextAdapter context, TextWriter writer, INode node)
{
try
{
/*
* it's possible the tree hasn't been parsed yet, so get
* the VMManager to parse and init it
*/
if (nodeTree != null)
{
if (!init_Renamed_Field)
{
nodeTree.init(context, rsvc);
init_Renamed_Field = true;
}
/*
* wrap the current context and add the VMProxyArg objects
*/
VMContext vmc = new VMContext(context, rsvc);
for (int i = 1; i < argArray.Length; i++)
{
/*
* we can do this as VMProxyArgs don't change state. They change
* the context.
*/
VMProxyArg arg = (VMProxyArg)proxyArgHash[argArray[i]];
vmc.AddVMProxyArg(arg);
}
/*
* now render the VM
*/
nodeTree.render(vmc, writer);
}
else
{
rsvc.error("VM error : " + macroName + ". Null AST");
}
}
catch (Exception e)
{
/*
* if it's a MIE, it came from the render.... throw it...
*/
if (e is MethodInvocationException)
{
throw (MethodInvocationException)e;
}
rsvc.error("VelocimacroProxy.render() : exception VM = #" + macroName + "() : " + StringUtils.stackTrace(e));
}
return(true);
}
/// <summary> returns the value of the reference. Generally, this is only
/// called for dynamic proxies, as the static ones should have
/// been stored in the VMContext's localcontext store
/// *
/// </summary>
/// <param name="context">Context to use for getting current value
/// </param>
/// <returns>Object value
/// *
///
/// </returns>
public Object getObject(InternalContextAdapter context)
{
try
{
/*
* we need to output based on our type
*/
Object retObject = null;
if (type == ParserTreeConstants.JJTREFERENCE)
{
/*
* two cases : scalar reference ($foo) or multi-level ($foo.bar....)
*/
if (numTreeChildren == 0)
{
/*
* if I am a single-level reference, can I not get get it out of my context?
*/
retObject = context.Get(singleLevelRef);
}
else
{
/*
* I need to let the AST produce it for me.
*/
retObject = nodeTree.execute(null, context);
}
}
else if (type == ParserTreeConstants.JJTOBJECTARRAY)
{
retObject = nodeTree.Value(context);
}
else if (type == ParserTreeConstants.JJTINTEGERRANGE)
{
retObject = nodeTree.Value(context);
}
else if (type == ParserTreeConstants.JJTTRUE)
{
retObject = staticObject;
}
else if (type == ParserTreeConstants.JJTFALSE)
{
retObject = staticObject;
}
else if (type == ParserTreeConstants.JJTSTRINGLITERAL)
{
retObject = nodeTree.Value(context);
}
else if (type == ParserTreeConstants.JJTNUMBERLITERAL)
{
retObject = staticObject;
}
else if (type == ParserTreeConstants.JJTTEXT)
{
/*
* this really shouldn't happen. text is just a thowaway arg for #foreach()
*/
try
{
StringWriter writer = new StringWriter();
nodeTree.render(context, writer);
retObject = writer;
}
catch (Exception e)
{
rsvc.error("VMProxyArg.getObject() : error rendering reference : " + e);
}
}
else if (type == GENERALSTATIC)
{
retObject = staticObject;
}
else
{
rsvc.error("Unsupported VM arg type : VM arg = " + callerReference + " type = " + type + "( VMProxyArg.getObject() )");
}
return(retObject);
}
catch (MethodInvocationException mie)
{
/*
* not ideal, but otherwise we propogate out to the
* VMContext, and the Context interface's put/get
* don't throw. So this is a the best compromise
* I can think of
*/
rsvc.error("VMProxyArg.getObject() : method invocation error getting value : " + mie);
return(null);
}
}
