public void addCompileWarning(String msg, ASTNode node) {
   Token token =
       new Token(Types.UNKNOWN, node.getText(), node.getLineNumber(), node.getColumnNumber());
   sourceUnit
       .getErrorCollector()
       .addWarning(WarningMessage.POSSIBLE_ERRORS, msg, token, sourceUnit);
 }
 private void addCompileError(String msg, ASTNode node) {
   SyntaxException se = new SyntaxException(msg, node.getLineNumber(), node.getColumnNumber());
   sourceUnit.getErrorCollector().addFatalError(new SyntaxErrorMessage(se, sourceUnit));
 }