Examples with BindingDescr org.drools.drl.ast.descr.BindingDescr used on opensource projects

Example 41 with BindingDescr

use of org.drools.drl.ast.descr.BindingDescr in project drools by kiegroup.

the class QueryElementBuilder method build.

public RuleConditionElement build(RuleBuildContext context, BaseDescr descr, QueryImpl query) {
    PatternDescr patternDescr = (PatternDescr) descr;
    Declaration[] params = query.getParameters();
    List<BaseDescr> args = (List<BaseDescr>) patternDescr.getDescrs();
    List<Declaration> requiredDeclarations = new ArrayList<>();
    ObjectType argsObjectType = ClassObjectType.ObjectArray_ObjectType;
    InternalReadAccessor arrayReader = new SelfReferenceClassFieldReader(Object[].class);
    Pattern pattern = new Pattern(context.getNextPatternId(), // tupleIndex is 0 by default
    0, // patternIndex is 0 by default
    0, argsObjectType, null);
    if (!StringUtils.isEmpty(patternDescr.getIdentifier())) {
        if (query.isAbductive()) {
            Declaration declr = context.getDeclarationResolver().getDeclaration(patternDescr.getIdentifier());
            if (declr != null && !patternDescr.isUnification()) {
                context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Duplicate declaration " + patternDescr.getIdentifier() + ", unable to bind abducted value"));
            }
        } else {
            context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Query binding is not supported by non-abductive queries : " + patternDescr.getIdentifier()));
        }
    }
    boolean addAbductiveReturnArgument = query.isAbductive() && !StringUtils.isEmpty(patternDescr.getIdentifier()) && args.size() < params.length;
    if (addAbductiveReturnArgument) {
        ExprConstraintDescr extraDescr = new ExprConstraintDescr(patternDescr.getIdentifier());
        extraDescr.setPosition(patternDescr.getConstraint().getDescrs().size());
        extraDescr.setType(ExprConstraintDescr.Type.POSITIONAL);
        args.add(extraDescr);
    }
    QueryArgument[] arguments = new QueryArgument[params.length];
    // Deal with the constraints, both positional and bindings
    for (BaseDescr base : args) {
        String expression = null;
        boolean isPositional = false;
        boolean isBinding = false;
        BindingDescr bind = null;
        ConstraintConnectiveDescr result = null;
        if (base instanceof BindingDescr) {
            bind = (BindingDescr) base;
            expression = bind.getVariable() + (bind.isUnification() ? " := " : " : ") + bind.getExpression();
            isBinding = true;
        } else {
            if (base instanceof ExprConstraintDescr) {
                ExprConstraintDescr ecd = (ExprConstraintDescr) base;
                expression = ecd.getExpression();
                isPositional = ecd.getType() == ExprConstraintDescr.Type.POSITIONAL;
            } else {
                expression = base.getText();
            }
            result = parseExpression(context, patternDescr, expression);
            if (result == null) {
                // error, can't parse expression.
                context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Unable to parse constraint: \n" + expression));
                continue;
            }
            isBinding = result.getDescrs().size() == 1 && result.getDescrs().get(0) instanceof BindingDescr;
            if (isBinding) {
                bind = (BindingDescr) result.getDescrs().get(0);
            }
        }
        if ((!isPositional) && (!isBinding)) {
            // error, can't have non binding slots.
            context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Query's must use positional or bindings, not field constraints:\n" + expression));
        } else if (isPositional && isBinding) {
            // error, can't have positional binding slots.
            context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Query's can't use positional bindings:\n" + expression));
        } else if (isPositional) {
            processPositional(context, query, params, arguments, requiredDeclarations, arrayReader, pattern, base, expression, result);
        } else {
            // it is binding
            processBinding(context, descr, params, arguments, requiredDeclarations, arrayReader, pattern, bind);
        }
    }
    List<Integer> varIndexList = new ArrayList<>();
    for (int i = 0; i < arguments.length; i++) {
        if (!(arguments[i] instanceof QueryArgument.Declr)) {
            if (arguments[i] instanceof QueryArgument.Var) {
                varIndexList.add(i);
            }
            continue;
        }
        Class actual = ((QueryArgument.Declr) arguments[i]).getArgumentClass();
        Declaration formalArgument = query.getParameters()[i];
        Class formal = formalArgument.getDeclarationClass();
        // input argument require a broader type, while output types require a narrower type, so we check for both.
        if (!ClassUtils.isTypeCompatibleWithArgumentType(actual, formal) && !ClassUtils.isTypeCompatibleWithArgumentType(formal, actual)) {
            context.addError(new DescrBuildError(context.getParentDescr(), descr, null, "Query is being invoked with known argument of type " + actual + " at position " + i + ", but the expected query argument is of type " + formal));
        }
    }
    return new QueryElement(pattern, query.getName(), arguments, toIntArray(varIndexList), requiredDeclarations.toArray(new Declaration[requiredDeclarations.size()]), !patternDescr.isQuery(), query.isAbductive());
}

Example 42 with BindingDescr

use of org.drools.drl.ast.descr.BindingDescr in project drools by kiegroup.

the class PatternBuilder method buildCcdDescr.

private Constraint buildCcdDescr(RuleBuildContext context, PatternDescr patternDescr, Declaration xpathStartDeclaration, Pattern pattern, BaseDescr d, ConstraintConnectiveDescr ccd, DumperContext mvelCtx) {
    d.copyLocation(patternDescr);
    mvelCtx.clear();
    String expr = DescrDumper.getInstance().dump(d, ccd, mvelCtx);
    Map<String, OperatorDescr> aliases = mvelCtx.getAliases();
    // create bindings
    TypeDeclaration typeDeclaration = getTypeDeclaration(pattern, context);
    for (BindingDescr bind : mvelCtx.getBindings()) {
        buildRuleBindings(context, patternDescr, xpathStartDeclaration, pattern, bind, typeDeclaration);
    }
    if (expr.length() == 0) {
        return null;
    }
    // check if it is an atomic expression
    Constraint constraint = processAtomicExpression(context, pattern, d, expr, aliases);
    // otherwise check if it is a simple expression
    return constraint != null ? constraint : buildExpression(context, pattern, d, expr, aliases, ccd.isNegated());
}