Examples with Equivalence com.google.common.base.Equivalence used on opensource projects

Example 1 with Equivalence

use of com.google.common.base.Equivalence in project grakn by graknlabs.

the class RuleUtils method getDependentRules.

/**
 * @param query top query
 * @return all rules that are reachable from the entry types
 */
public static Set<InferenceRule> getDependentRules(ReasonerQueryImpl query) {
    final Equivalence<Atom> equivalence = new Equivalence<Atom>() {

        @Override
        protected boolean doEquivalent(Atom a1, Atom a2) {
            return a1.isAlphaEquivalent(a2);
        }

        @Override
        protected int doHash(Atom a) {
            return a.alphaEquivalenceHashCode();
        }
    };
    Set<InferenceRule> rules = new HashSet<>();
    Set<Equivalence.Wrapper<Atom>> visitedAtoms = new HashSet<>();
    Stack<Equivalence.Wrapper<Atom>> atoms = new Stack<>();
    query.selectAtoms().stream().map(equivalence::wrap).forEach(atoms::push);
    while (!atoms.isEmpty()) {
        Equivalence.Wrapper<Atom> wrappedAtom = atoms.pop();
        Atom atom = wrappedAtom.get();
        if (!visitedAtoms.contains(wrappedAtom) && atom != null) {
            atom.getApplicableRules().peek(rules::add).flatMap(rule -> rule.getBody().selectAtoms().stream()).map(equivalence::wrap).filter(at -> !visitedAtoms.contains(at)).filter(at -> !atoms.contains(at)).forEach(atoms::add);
            visitedAtoms.add(wrappedAtom);
        }
    }
    return rules;
}