Examples with ParserRuleContext org.antlr.v4.runtime.ParserRuleContext used on opensource projects

Example 6 with ParserRuleContext

use of org.antlr.v4.runtime.ParserRuleContext in project antlr4 by antlr.

the class ParseTreePatternMatcher method matchImpl.

// ---- SUPPORT CODE ----
/**
	 * Recursively walk {@code tree} against {@code patternTree}, filling
	 * {@code match.}{@link ParseTreeMatch#labels labels}.
	 *
	 * @return the first node encountered in {@code tree} which does not match
	 * a corresponding node in {@code patternTree}, or {@code null} if the match
	 * was successful. The specific node returned depends on the matching
	 * algorithm used by the implementation, and may be overridden.
	 */
protected ParseTree matchImpl(ParseTree tree, ParseTree patternTree, MultiMap<String, ParseTree> labels) {
    if (tree == null) {
        throw new IllegalArgumentException("tree cannot be null");
    }
    if (patternTree == null) {
        throw new IllegalArgumentException("patternTree cannot be null");
    }
    // x and <ID>, x and y, or x and x; or could be mismatched types
    if (tree instanceof TerminalNode && patternTree instanceof TerminalNode) {
        TerminalNode t1 = (TerminalNode) tree;
        TerminalNode t2 = (TerminalNode) patternTree;
        ParseTree mismatchedNode = null;
        // both are tokens and they have same type
        if (t1.getSymbol().getType() == t2.getSymbol().getType()) {
            if (t2.getSymbol() instanceof TokenTagToken) {
                // x and <ID>
                TokenTagToken tokenTagToken = (TokenTagToken) t2.getSymbol();
                // track label->list-of-nodes for both token name and label (if any)
                labels.map(tokenTagToken.getTokenName(), tree);
                if (tokenTagToken.getLabel() != null) {
                    labels.map(tokenTagToken.getLabel(), tree);
                }
            } else if (t1.getText().equals(t2.getText())) {
            // x and x
            } else {
                // x and y
                if (mismatchedNode == null) {
                    mismatchedNode = t1;
                }
            }
        } else {
            if (mismatchedNode == null) {
                mismatchedNode = t1;
            }
        }
        return mismatchedNode;
    }
    if (tree instanceof ParserRuleContext && patternTree instanceof ParserRuleContext) {
        ParserRuleContext r1 = (ParserRuleContext) tree;
        ParserRuleContext r2 = (ParserRuleContext) patternTree;
        ParseTree mismatchedNode = null;
        // (expr ...) and <expr>
        RuleTagToken ruleTagToken = getRuleTagToken(r2);
        if (ruleTagToken != null) {
            ParseTreeMatch m = null;
            if (r1.getRuleContext().getRuleIndex() == r2.getRuleContext().getRuleIndex()) {
                // track label->list-of-nodes for both rule name and label (if any)
                labels.map(ruleTagToken.getRuleName(), tree);
                if (ruleTagToken.getLabel() != null) {
                    labels.map(ruleTagToken.getLabel(), tree);
                }
            } else {
                if (mismatchedNode == null) {
                    mismatchedNode = r1;
                }
            }
            return mismatchedNode;
        }
        // (expr ...) and (expr ...)
        if (r1.getChildCount() != r2.getChildCount()) {
            if (mismatchedNode == null) {
                mismatchedNode = r1;
            }
            return mismatchedNode;
        }
        int n = r1.getChildCount();
        for (int i = 0; i < n; i++) {
            ParseTree childMatch = matchImpl(r1.getChild(i), patternTree.getChild(i), labels);
            if (childMatch != null) {
                return childMatch;
            }
        }
        return mismatchedNode;
    }
    // if nodes aren't both tokens or both rule nodes, can't match
    return tree;
}

Example 7 with ParserRuleContext

use of org.antlr.v4.runtime.ParserRuleContext in project antlr4 by antlr.

the class XPath method evaluate.

/**
	 * Return a list of all nodes starting at {@code t} as root that satisfy the
	 * path. The root {@code /} is relative to the node passed to
	 * {@link #evaluate}.
	 */
public Collection<ParseTree> evaluate(final ParseTree t) {
    ParserRuleContext dummyRoot = new ParserRuleContext();
    // don't set t's parent.
    dummyRoot.children = Collections.singletonList(t);
    Collection<ParseTree> work = Collections.<ParseTree>singleton(dummyRoot);
    int i = 0;
    while (i < elements.length) {
        Collection<ParseTree> next = new LinkedHashSet<ParseTree>();
        for (ParseTree node : work) {
            if (node.getChildCount() > 0) {
                // only try to match next element if it has children
                // e.g., //func/*/stat might have a token node for which
                // we can't go looking for stat nodes.
                Collection<? extends ParseTree> matching = elements[i].evaluate(node);
                next.addAll(matching);
            }
        }
        i++;
        work = next;
    }
    return work;
}

Example 8 with ParserRuleContext

use of org.antlr.v4.runtime.ParserRuleContext in project antlr4 by antlr.

the class Parser method isExpectedToken.

/**
	 * Checks whether or not {@code symbol} can follow the current state in the
	 * ATN. The behavior of this method is equivalent to the following, but is
	 * implemented such that the complete context-sensitive follow set does not
	 * need to be explicitly constructed.
	 *
	 * <pre>
	 * return getExpectedTokens().contains(symbol);
	 * </pre>
	 *
	 * @param symbol the symbol type to check
	 * @return {@code true} if {@code symbol} can follow the current state in
	 * the ATN, otherwise {@code false}.
	 */
public boolean isExpectedToken(int symbol) {
    //   		return getInterpreter().atn.nextTokens(_ctx);
    ATN atn = getInterpreter().atn;
    ParserRuleContext ctx = _ctx;
    ATNState s = atn.states.get(getState());
    IntervalSet following = atn.nextTokens(s);
    if (following.contains(symbol)) {
        return true;
    }
    //        System.out.println("following "+s+"="+following);
    if (!following.contains(Token.EPSILON))
        return false;
    while (ctx != null && ctx.invokingState >= 0 && following.contains(Token.EPSILON)) {
        ATNState invokingState = atn.states.get(ctx.invokingState);
        RuleTransition rt = (RuleTransition) invokingState.transition(0);
        following = atn.nextTokens(rt.followState);
        if (following.contains(symbol)) {
            return true;
        }
        ctx = (ParserRuleContext) ctx.parent;
    }
    if (following.contains(Token.EPSILON) && symbol == Token.EOF) {
        return true;
    }
    return false;
}

Example 9 with ParserRuleContext

use of org.antlr.v4.runtime.ParserRuleContext in project antlr4 by antlr.

the class ParserInterpreter method visitRuleStopState.

protected void visitRuleStopState(ATNState p) {
    RuleStartState ruleStartState = atn.ruleToStartState[p.ruleIndex];
    if (ruleStartState.isLeftRecursiveRule) {
        Pair<ParserRuleContext, Integer> parentContext = _parentContextStack.pop();
        unrollRecursionContexts(parentContext.a);
        setState(parentContext.b);
    } else {
        exitRule();
    }
    RuleTransition ruleTransition = (RuleTransition) atn.states.get(getState()).transition(0);
    setState(ruleTransition.followState.stateNumber);
}

Example 10 with ParserRuleContext

use of org.antlr.v4.runtime.ParserRuleContext in project antlr4 by antlr.

the class ParserRuleContext method addChild.

/** Add a child to this node based upon matchedToken. It
	 *  creates a TerminalNodeImpl rather than using
	 *  {@link Parser#createTerminalNode(ParserRuleContext, Token)}. I'm leaving this
     *  in for compatibility but the parser doesn't use this anymore.
	 */
@Deprecated
public TerminalNode addChild(Token matchedToken) {
    TerminalNodeImpl t = new TerminalNodeImpl(matchedToken);
    addAnyChild(t);
    t.setParent(this);
    return t;
}