ParseTrees.java 文件源码

@CheckForNull
public static RuleNode findAncestor(@NonNull ParseTree tree, @NonNull BitSet ruleIndexes) {
    for (ParseTree current = tree; current != null; current = current.getParent()) {
        if (!(current instanceof RuleNode)) {
            continue;
        }

        RuleNode ruleNode = (RuleNode)current;
        int ruleIndex = ruleNode.getRuleContext().getRuleIndex();
        if (ruleIndex < 0) {
            continue;
        }

        if (ruleIndexes.get(ruleIndex)) {
            return ruleNode;
        }
    }

    return null;
}