/**
* Resolve a simple or qualified rule name as a full rule name.
*
* @param ruleName
* the name of the rule.
*/
public JSGFRuleName Resolve(JSGFRuleName ruleName)
{
// System.out.println ("Resolving " + ruleName);
JSGFRuleName rn = new JSGFRuleName(ruleName.GetRuleName());
String simpleName = rn.GetSimpleRuleName();
String grammarName = rn.GetSimpleGrammarName();
String packageName = rn.GetPackageName();
String fullGrammarName = rn.GetFullGrammarName();
// Check for badly formed RuleName
if (packageName != null && grammarName == null)
{
throw new JSGFGrammarException("Error: badly formed rulename " + rn);
}
if (ruleName.GetSimpleRuleName().Equals("NULL"))
{
return(JSGFRuleName.Null);
}
if (ruleName.GetSimpleRuleName().Equals("VOID"))
{
return(JSGFRuleName.Void);
}
// Check simple case: a local rule reference
if (fullGrammarName == null && GetRule(simpleName) != null)
{
return(new JSGFRuleName(_name + '.' + simpleName));
}
// Check for fully-qualified reference
if (fullGrammarName != null)
{
JSGFRuleGrammar g = _manager.RetrieveGrammar(fullGrammarName);
if (g != null)
{
if (g.GetRule(simpleName) != null)
{
// we have a successful resolution
return(new JSGFRuleName(fullGrammarName + '.' + simpleName));
}
}
}
// Collect all matching imports into a list. After trying to
// match rn to each import statement the vec will have
// size()=0 if rn is unresolvable
// size()=1 if rn is properly resolvable
// size()>1 if rn is an ambiguous reference
List <JSGFRuleName> matches = new List <JSGFRuleName>();
// Get list of imports
// Add local grammar to simply the case of checking for
// a qualified or fully-qualified local reference.
List <JSGFRuleName> imports = new List <JSGFRuleName>(this.Imports);
imports.Add(new JSGFRuleName(_name + ".*"));
// Check each import statement for a possible match
foreach (JSGFRuleName importName in imports)
{
// TO-DO: update for JSAPI 1.0
String importSimpleName = importName.GetSimpleRuleName();
String importGrammarName = importName.GetSimpleGrammarName();
String importFullGrammarName = importName.GetFullGrammarName();
// Check for badly formed import name
if (importFullGrammarName == null)
{
throw new JSGFGrammarException("Error: badly formed import " + ruleName);
}
// Get the imported grammar
JSGFRuleGrammar gref = _manager.RetrieveGrammar(importFullGrammarName);
if (gref == null)
{
Console.WriteLine("Warning: import of unknown grammar " + ruleName + " in " + _name);
continue;
}
// If import includes simpleName, test that it really exists
if (!importSimpleName.Equals("*") && gref.GetRule(importSimpleName) == null)
{
Console.WriteLine("Warning: import of undefined rule " + ruleName + " in " + _name);
continue;
}
// Check for fully-qualified or qualified reference
if (importFullGrammarName.Equals(fullGrammarName) || importGrammarName.Equals(fullGrammarName))
{
// Know that either
// import <ipkg.igram.???> matches <pkg.gram.???>
// OR
// import <ipkg.igram.???> matches <gram.???>
// (ipkg may be null)
if (importSimpleName.Equals("*"))
{
if (gref.GetRule(simpleName) != null)
{
// import <pkg.gram.*> matches <pkg.gram.rulename>
matches.Add(new JSGFRuleName(importFullGrammarName + '.' + simpleName));
}
continue;
}
else
{
// Now testing
// import <ipkg.igram.iRuleName> against <??.gram.ruleName>
//
if (importSimpleName.Equals(simpleName))
{
// import <pkg.gram.rulename> exact match for
// <???.gram.rulename>
matches.Add(new JSGFRuleName(importFullGrammarName + '.' + simpleName));
}
continue;
}
}
// If we get here and rulename is qualified or fully-qualified
// then the match failed - try the next import statement
if (fullGrammarName != null)
{
continue;
}
// Now test
// import <ipkg.igram.*> against <simpleName>
if (importSimpleName.Equals("*"))
{
if (gref.GetRule(simpleName) != null)
{
// import <pkg.gram.*> matches <simpleName>
matches.Add(new JSGFRuleName(importFullGrammarName + '.' + simpleName));
}
continue;
}
// Finally test
// import <ipkg.igram.iSimpleName> against <simpleName>
if (importSimpleName.Equals(simpleName))
{
matches.Add(new JSGFRuleName(importFullGrammarName + '.' + simpleName));
continue;
}
}
// The return behavior depends upon number of matches
switch (matches.Count)
{
case 0: // Return null if rulename is unresolvable
return(null);
case 1: // Return successfully
return(matches[0]);
default: // Throw exception if ambiguous reference
StringBuilder b = new StringBuilder();
b.Append("Warning: ambiguous reference ").Append(rn).Append(" in ").Append(_name).Append(" to ");
foreach (JSGFRuleName tmp in matches)
{
b.Append(tmp).Append(" and ");
}
b.Length = (b.Length - 5);
throw new JSGFGrammarException(b.ToString());
}
}