public ATN createATN() {
_createATN(g.rules.values());
atn.maxTokenType = g.getMaxTokenType();
addRuleFollowLinks();
addEOFTransitionToStartRules();
return atn;
}
public ParserATNFactory(@NotNull Grammar g) {
if (g == null) {
throw new NullPointerException("g");
}
this.g = g;
ATNType atnType = g instanceof LexerGrammar ? ATNType.LEXER : ATNType.PARSER;
int maxTokenType = g.getMaxTokenType();
this.atn = new ATN(atnType, maxTokenType);
}
@NotNull
@Override
public ATN createATN() {
_createATN(g.rules.values());
assert atn.maxTokenType == g.getMaxTokenType();
addRuleFollowLinks();
addEOFTransitionToStartRules();
ATNOptimizer.optimize(g, atn);
for (Triple<Rule, ATNState, ATNState> pair : preventEpsilonClosureBlocks) {
LL1Analyzer analyzer = new LL1Analyzer(atn);
if (analyzer.LOOK(pair.b, pair.c, null).contains(org.antlr.v4.runtime.Token.EPSILON)) {
ErrorType errorType =
pair.a instanceof LeftRecursiveRule
? ErrorType.EPSILON_LR_FOLLOW
: ErrorType.EPSILON_CLOSURE;
g.tool.errMgr.grammarError(
errorType, g.fileName, ((GrammarAST) pair.a.ast.getChild(0)).getToken(), pair.a.name);
}
}
optionalCheck:
for (Triple<Rule, ATNState, ATNState> pair : preventEpsilonOptionalBlocks) {
int bypassCount = 0;
for (int i = 0; i < pair.b.getNumberOfTransitions(); i++) {
ATNState startState = pair.b.transition(i).target;
if (startState == pair.c) {
bypassCount++;
continue;
}
LL1Analyzer analyzer = new LL1Analyzer(atn);
if (analyzer.LOOK(startState, pair.c, null).contains(org.antlr.v4.runtime.Token.EPSILON)) {
g.tool.errMgr.grammarError(
ErrorType.EPSILON_OPTIONAL,
g.fileName,
((GrammarAST) pair.a.ast.getChild(0)).getToken(),
pair.a.name);
continue optionalCheck;
}
}
if (bypassCount != 1) {
throw new UnsupportedOperationException(
"Expected optional block with exactly 1 bypass alternative.");
}
}
return atn;
}
/**
* From set build single edge graph o->o-set->o. To conform to what an alt block looks like, must
* have extra state on left. This handles ~A also, converted to ~{A} set.
*/
public Handle set(GrammarAST associatedAST, List<GrammarAST> terminals, boolean invert) {
ATNState left = newState(associatedAST);
ATNState right = newState(associatedAST);
IntervalSet set = new IntervalSet();
for (GrammarAST t : terminals) {
int ttype = g.getTokenType(t.getText());
set.add(ttype);
}
if (invert) {
IntervalSet notSet = set.complement(Token.MIN_TOKEN_TYPE, g.getMaxTokenType());
left.addTransition(new NotSetTransition(right, set, notSet));
} else {
left.addTransition(new SetTransition(right, set));
}
associatedAST.atnState = left;
return new Handle(left, right);
}
