public String getRecognizerFileName(SourceType sourceType) {
		ST extST = getTemplates().getInstanceOf("codeFileExtension");
		String recognizerName = gen.g.getRecognizerName();
		return recognizerName+extST.render();
	}
Generate TParser.java and TLexer.java from T.g4 if combined, else
 just use T.java as output regardless of type.
tool/src/org/antlr/v4/codegen/Target.java