Examples with BacktrackException fr.lirmm.graphik.graal.homomorphism.BacktrackException used on opensource projects

Example 6 with BacktrackException

use of fr.lirmm.graphik.graal.homomorphism.BacktrackException in project graal by graphik-team.

the class SimpleFC method getCandidatsIterator.

@Override
public CloseableIterator<Term> getCandidatsIterator(AtomSet g, Var var, Substitution initialSubstitution, Map<Variable, Integer> map, Var[] varData, RulesCompilation rc) throws BacktrackException {
    HomomorphismIteratorChecker tmp;
    try {
        tmp = new HomomorphismIteratorChecker(var, g.termsIterator(), var.shared.preAtoms, g, initialSubstitution, map, varData, rc);
    } catch (AtomSetException e) {
        throw new BacktrackException(e);
    }
    tmp.setProfiler(this.getProfiler());
    return tmp;
}

Example 7 with BacktrackException

use of fr.lirmm.graphik.graal.homomorphism.BacktrackException in project graal by graphik-team.

the class NFC2 method checkForward.

// /////////////////////////////////////////////////////////////////////////
// PUBLIC METHODS
// /////////////////////////////////////////////////////////////////////////
@Override
public boolean checkForward(Var v, AtomSet g, Substitution initialSubstitution, Map<Variable, Integer> map, Var[] varData, RulesCompilation rc) throws BacktrackException {
    // clear all computed candidats for post variables
    for (VarSharedData z : v.shared.postVars) {
        this.clear(v.shared, z);
    }
    Var varToAssign = null;
    for (Atom atom : v.shared.postAtoms) {
        boolean runCheck = true;
        if (checkMode) {
            int i = 0;
            for (Variable t : atom.getVariables()) {
                Integer idx = map.get(t);
                if (idx != null) {
                    Var z = varData[idx];
                    if (z.shared.level > v.shared.level) {
                        ++i;
                        varToAssign = z;
                        if (i > 1 || !this.data[z.shared.level].candidats[v.shared.level].init) {
                            runCheck = false;
                            break;
                        }
                    }
                }
            }
        }
        if (checkMode && runCheck) {
            try {
                if (!check(atom, v.shared, varToAssign.shared, g, initialSubstitution, map, varData, rc)) {
                    return false;
                }
            } catch (AtomSetException e) {
                throw new BacktrackException("An error occurs while checking current candidate");
            }
        } else {
            try {
                if (!select(atom, v, g, initialSubstitution, map, varData, rc)) {
                    return false;
                }
            } catch (IteratorException e) {
                throw new BacktrackException("An error occurs while selecting candidates for next steps ");
            } catch (AtomSetException e) {
                throw new BacktrackException("An error occurs while selecting candidates for next steps ");
            }
        }
    }
    return true;
}

Example 8 with BacktrackException

use of fr.lirmm.graphik.graal.homomorphism.BacktrackException in project graal by graphik-team.

the class NoForwardChecking method getCandidatsIterator.

@Override
public CloseableIterator<Term> getCandidatsIterator(AtomSet g, Var var, Substitution initialSubstitution, Map<Variable, Integer> map, Var[] varData, RulesCompilation rc) throws BacktrackException {
    HomomorphismIteratorChecker tmp;
    try {
        tmp = new HomomorphismIteratorChecker(var, g.termsIterator(), var.shared.preAtoms, g, initialSubstitution, map, varData, rc);
    } catch (AtomSetException e) {
        throw new BacktrackException(e);
    }
    tmp.setProfiler(this.getProfiler());
    return tmp;
}

Example 9 with BacktrackException

use of fr.lirmm.graphik.graal.homomorphism.BacktrackException in project graal by graphik-team.

the class DefaultBootstrapper method exec.

// /////////////////////////////////////////////////////////////////////////
// 
// /////////////////////////////////////////////////////////////////////////
@Override
public CloseableIterator<Term> exec(final VarSharedData v, Collection<Atom> preAtoms, Collection<Atom> postAtoms, final AtomSet data, RulesCompilation compilation) throws BacktrackException {
    Iterator<Atom> it = postAtoms.iterator();
    if (it.hasNext()) {
        Atom a = it.next();
        final Iterator<Pair<Atom, Substitution>> rewritingOf = compilation.getRewritingOf(a).iterator();
        // TODO refactor the following code using converter Iterator or
        // create a private class?
        CloseableIterator<CloseableIterator<Term>> metaIt = new AbstractCloseableIterator<CloseableIterator<Term>>() {

            CloseableIterator<Term> next = null;

            @Override
            public void close() {
                if (next != null)
                    this.next.close();
            }

            @Override
            public boolean hasNext() throws IteratorException {
                try {
                    if (next == null && rewritingOf.hasNext()) {
                        Pair<Atom, Substitution> rew = rewritingOf.next();
                        Atom im = rew.getLeft();
                        Predicate predicate = im.getPredicate();
                        int pos = im.indexOf(rew.getRight().createImageOf(v.value));
                        next = data.termsByPredicatePosition(predicate, pos);
                    }
                } catch (AtomSetException e) {
                    throw new IteratorException("An errors occurs while getting terms by predicate position", e);
                }
                return next != null;
            }

            @Override
            public CloseableIterator<Term> next() throws IteratorException {
                if (next == null)
                    this.hasNext();
                CloseableIterator<Term> ret = next;
                next = null;
                return ret;
            }
        };
        return new CloseableIteratorAggregator<Term>(metaIt);
    } else {
        try {
            return data.termsIterator();
        } catch (AtomSetException e) {
            throw new BacktrackException(e);
        }
    }
}

Example 10 with BacktrackException

use of fr.lirmm.graphik.graal.homomorphism.BacktrackException in project graal by graphik-team.

the class RestrictedChaseHaltingCondition method apply.

@Override
public CloseableIterator<Atom> apply(Rule rule, Substitution substitution, AtomSet data) throws HomomorphismFactoryException, HomomorphismException {
    InMemoryAtomSet newFacts = substitution.createImageOf(rule.getHead());
    ConjunctiveQuery query = new ConjunctiveQueryWithFixedVariables(newFacts, substitution.createImageOf(rule.getFrontier()));
    try {
        if (SmartHomomorphism.instance().execute(query, data).hasNext()) {
            return new CloseableIteratorAdapter<Atom>(Collections.<Atom>emptyList().iterator());
        }
    } catch (IteratorException e) {
        throw new HomomorphismException("An errors occurs while iterating results", e);
    } catch (BacktrackException e) {
        throw new HomomorphismException("An errors occurs while iterating results", e);
    }
    // replace variables by fresh symbol
    for (Variable t : rule.getExistentials()) {
        substitution.put(t, data.getFreshSymbolGenerator().getFreshSymbol());
    }
    CloseableIteratorWithoutException<Atom> it = substitution.createImageOf(rule.getHead()).iterator();
    return it;
}