/*
* This method overrides the superclass method in order to calls the parser which is
* in charge of extracting the particular CST of a provided file.
* It requires the existence of the Parser/Lexer of the grammar in the classpath
*
* @see gts.modernization.launcher.Gra2MoLAbstractLauncher#parser(java.lang.String)
*/
@Override
protected Element parser(File path) {
Object result = null;
try {
// Create the filestream
ANTLRFileStream afs;
if (!caseSensitive) {
Gra2MoLLogger.getInstance().print("Creating non case sensitive parser for " + path);
afs = new ANTLRNoCaseFileStream(path.getAbsolutePath());
} else {
Gra2MoLLogger.getInstance().print("Creating case sensitive parser for " + path);
afs = new ANTLRFileStream(path.getAbsolutePath());
}
// Create the lexer class
Class lexer = Class.forName(grammarName + "Lexer");
// Locate the lexer constructor
Constructor lexerConstructor = lexer.getConstructor(org.antlr.runtime.CharStream.class);
// Create the lexer instance
Lexer lexerInstance = (Lexer) lexerConstructor.newInstance((CharStream) afs);
// Create the token stream
CommonTokenStream cts = new CommonTokenStream(lexerInstance);
// Create the parser class
Class parser = Class.forName(grammarName + "Parser");
// Locate the parser constructor
Constructor parserConstructor = parser.getConstructor(org.antlr.runtime.TokenStream.class);
// Create the parser instance
Object parserInstance = parserConstructor.newInstance(cts);
// Locate the method
Method method = parser.getMethod(grammarMainRule, null);
// Invoke the method
Object returnedValue = method.invoke(parserInstance, null);
// Extracts the returnNode field
Class returned = returnedValue.getClass();
Field field = returned.getField("returnNode");
result = field.get(returnedValue);
} catch (Exception e) {
System.err.println("Error parsing the file " + path);
e.printStackTrace();
}
if (result instanceof Node) {
Node n = (Node) result;
return n;
} else {
return null;
}
}
/**
* Offers a method to the subclasses to print in the logger
*
* @param msg
*/
public void printError(String msg) {
Gra2MoLLogger.getInstance().print("<Extension Error: " + msg + ">");
}