rqlparser.java

这是外国一个开源推理机

        ResourceQuery q;
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case IDENTIFIER:
    case CLASSVAR:
    case PROPERTYVAR:
      q = var();
                       {if (true) return q;}
      break;
    case NULL:
      q = null_value();
                           {if (true) return q;}
      break;
    case URI:
      q = uri();
                       {if (true) return q;}
      break;
    case DOMAIN:
      q = domain();
                       {if (true) return q;}
      break;
    case RANGE:
      q = range();
                       {if (true) return q;}
      break;
    case SUBCLASSOF:
      q = subClassOf();
                           {if (true) return q;}
      break;
    case SUBPROPERTYOF:
      q = subPropertyOf();
                              {if (true) return q;}
      break;
    case TYPEOF:
      q = typeOf();
                       {if (true) return q;}
      break;
    case SUPERPROPERTYOF:
      q = superPropertyOf();
                                {if (true) return q;}
      break;
    case SUPERCLASSOF:
      q = superClassOf();
                             {if (true) return q;}
      break;
    default:
      jj_la1[7] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
    throw new Error("Missing return statement in function");
  }

  final public DataVar null_value() throws ParseException {
    Token t;
    t = jj_consume_token(NULL);
        // FIXME a null token is now returned as a DataVar, because there is
        // no specific 'nulltoken' object in the data model. should we change
        // this?
        {if (true) return new DataVar(t.image);}
    throw new Error("Missing return statement in function");
  }

  final public void rangeslist(List selectors) throws ParseException {
    ranges_elem(selectors);
    label_3:
    while (true) {
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case COMMA:
        ;
        break;
      default:
        jj_la1[8] = jj_gen;
        break label_3;
      }
      jj_consume_token(COMMA);
      ranges_elem(selectors);
    }
  }

  final public void ranges_elem(List selectors) throws ParseException {
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case CLASS:
    case PROPERTY:
      class_or_property_selector(selectors);
      break;
    case LBRACE:
    case TYPEOF:
    case SUBCLASSOF:
    case SUPERCLASSOF:
    case SUBPROPERTYOF:
    case SUPERPROPERTYOF:
    case DOMAIN:
    case RANGE:
    case CLASSVAR:
    case PROPERTYVAR:
    case URI:
      pathexpr(selectors);
      break;
    default:
      jj_la1[9] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

  final public void class_or_property_selector(List selectors) throws ParseException {
        RdfsClass rdfsClass;
        ClassVar classVar;
        RdfProperty rdfProperty;
        PropertyVar propVar;
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case CLASS:
      rdfsClass = rdfs_class();
      jj_consume_token(LBRACE);
      classVar = classvar();
      jj_consume_token(RBRACE);
                ClassSelector classSel = new ClassSelector(classVar, rdfsClass);
                _unboundVarList.remove(classVar);
                selectors.add(classSel);
      break;
    case PROPERTY:
      rdfProperty = rdf_property();
      jj_consume_token(LBRACE);
      propVar = propertyvar();
      jj_consume_token(RBRACE);
                PropertySelector propSel = new PropertySelector(propVar, rdfProperty);
                _unboundVarList.remove(propVar);
                selectors.add(propSel);
      break;
    default:
      jj_la1[10] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

  final public void pathexpr(List selectors) throws ParseException {
        // Vars for implicit joins between path elements
        FromTo fromTo = new FromTo();
    fromTo = first_pathelem(selectors);
    label_4:
    while (true) {
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case DOT:
        ;
        break;
      default:
        jj_la1[11] = jj_gen;
        break label_4;
      }
      fromTo = joined_pathelem(selectors, fromTo);
    }
  }

/* The first path element of a row (possibly) */
  final public FromTo first_pathelem(List selectors) throws ParseException {
        FromTo sourceFromTo = null;
        FromTo targetFromTo = null;

        PropertyQuery propQ = null;
        ClassQuery classQ = null;
        URI uri = null;
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case LBRACE:
      jj_consume_token(LBRACE);
      sourceFromTo = from_to(selectors);
      jj_consume_token(RBRACE);
      break;
    default:
      jj_la1[12] = jj_gen;
      ;
    }
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case PROPERTY:
    case SUBPROPERTYOF:
    case SUPERPROPERTYOF:
    case PROPERTYVAR:
      propQ = property_query();
      break;
    case CLASS:
    case TYPEOF:
    case SUBCLASSOF:
    case SUPERCLASSOF:
    case DOMAIN:
    case RANGE:
    case CLASSVAR:
      classQ = class_query();
      break;
    case URI:
      uri = uri();
      break;
    default:
      jj_la1[13] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case LBRACE:
      jj_consume_token(LBRACE);
      targetFromTo = from_to(selectors);
      jj_consume_token(RBRACE);
      break;
    default:
      jj_la1[14] = jj_gen;
      ;
    }
                if (classQ != null) {
                        if (targetFromTo == null) {
                                {if (true) throw new ParseException("from_to part missing for " +
                                                classQ.toString());}
                        }
                        if (sourceFromTo != null) {
                                {if (true) throw new ParseException("Not a property query: " +
                                                classQ.toString());}
                        }
                        if (targetFromTo.dataVar == null) {
                                if (targetFromTo.classQ == null) {
                                        {if (true) throw new ParseException("Data or class var missing for " +
                                                        classQ.toString());}
                                }
                                else if (targetFromTo.classQ instanceof ClassVar) {
                                        // Query like: classQ { : $X}
                                        ClassSelector classSel = new
                                                ClassSelector((ClassVar)targetFromTo.classQ, classQ);
                                        _unboundVarList.remove(targetFromTo.classQ);
                                        _unboundVarList.remove(classQ);
                                        selectors.add(classSel);
                                }
                                else {
                                        {if (true) throw new ParseException("target should be class var for " +
                                                        classQ.toString());}
                                }
                        }
                        else {
                                // Query like: classQ {X}
                                InstanceSelector insSel = new InstanceSelector(
                                                targetFromTo.dataVar, classQ, false);
                                _unboundVarList.remove(targetFromTo.dataVar);
                                _unboundVarList.remove(classQ);
                                selectors.add(insSel);
                        }
                }
                else if (uri != null) {

                        if (sourceFromTo == null &&
                            targetFromTo != null &&
                            targetFromTo.classQ != null &&
                            targetFromTo.classQ instanceof ClassVar)
                        {
                                // query is of the form 'uri{ : $X}' or 'uri{X : $X}'

                                // FIXME what if targetFromTo.classQ is not just a var?

                                // create a class selector constraining $X to subclasses
                                // of uri. FIXME currently subClassOf(X) does not return X
                                // itself, this is necessary here.
                                classQ = new SubClassOf((ClassQuery)uri, true);
                                ClassSelector classSel = new ClassSelector((ClassVar)targetFromTo.classQ, classQ);
                                _unboundVarList.remove(targetFromTo.classQ);
                                _unboundVarList.remove(classQ);
                                selectors.add(classSel);

                                if (targetFromTo.dataVar != null) {
                                        InstanceSelector instSel = new InstanceSelector(targetFromTo.dataVar, targetFromTo.classQ, true);
                                        _unboundVarList.remove(targetFromTo.dataVar);
                                        _unboundVarList.remove(targetFromTo.classQ);
                                        selectors.add(instSel);
                                }
                        }
                        else if (sourceFromTo != null ||
                                 targetFromTo == null ||        // implicit join using "."
                                 targetFromTo.dataVar == null || // schema path selector
                                 targetFromTo.classQ != null)    // schema path selector
                        {
                                // This is a property selector. This will be handled in
                                // the next if-statement
                                propQ = (PropertyQuery)uri;
                        }
                        else {
                                // Don't know what kind of selector this is, use an
                                // UnknownSelector
                                UnknownSelector unknownSel = new UnknownSelector(
                                                uri, targetFromTo.dataVar);
                                _unboundVarList.remove(targetFromTo.dataVar);
                                selectors.add(unknownSel);
                        }
                }
                // Not 'else if' because propQ can be set later in case of uri !!!
                if (propQ != null) {
                        // Both FromTo's are needed:
                        if (sourceFromTo == null) {
                                sourceFromTo = new FromTo();
                        }
                        if (targetFromTo == null) {
                                targetFromTo = new FromTo();
                        }

                        // In case just one of the FromTo's has a dataVar, the other
                        // should get an anonymous DataVar.
                        if (sourceFromTo.dataVar != null) {
                                if (targetFromTo.dataVar == null) {
                                        targetFromTo.dataVar = new DataVar(getAnonymousVarName());

                                        if (targetFromTo.classQ != null) {
                                                // We've created a new class restriction
                                                InstanceSelector resSel = new InstanceSelector(
                                                                targetFromTo.dataVar, targetFromTo.classQ,
                                                                true);
                                                _unboundVarList.remove(targetFromTo.classQ);
                                                selectors.add(resSel);
                                        }
                                }
                        }
                        else { // sourceFromTo.dataVar == null
                                if (targetFromTo.dataVar != null) {
                                        sourceFromTo.dataVar = new DataVar(getAnonymousVarName());

                                        if (sourceFromTo.classQ != null) {
                                                // We've created a new class restriction
                                                InstanceSelector resSel = new InstanceSelector(
                                                                sourceFromTo.dataVar, sourceFromTo.classQ,
                                                                true);
                                                _unboundVarList.remove(sourceFromTo.classQ);
                                                selectors.add(resSel);
                                        }
                                }
                        }

                        // Now both FromTo's are ensured to be complete


                        // Create a property selector for the property in case propQ
                        // is not a PropertyVar itself
                        PropertyVar propVar = null;
                        if (propQ instanceof PropertyVar) {
                                propVar = (PropertyVar)propQ;
                                // If both source and target are empty
                                // (e.g. {} @P {} ), we still need a
                                // property selector.
                                if (sourceFromTo.dataVar == null &&
                                    targetFromTo.dataVar == null)
                                {
                                    PropertySelector propSel =
                                        new PropertySelector(propVar, new RdfProperty());
                                    _unboundVarList.remove(propVar);
                                    selectors.add(propSel);
                                }
                        }
                        else {
                                // Use anonymous var that can be shared with other selectors
                                propVar = new PropertyVar(getAnonymousVarName());
                                PropertySelector propSel = new PropertySelector(propVar, propQ);
                                _unboundVarList.remove(propQ);
                                selectors.add(propSel);
                        }


                        // If appropriate, create DataPathSelector
                        if (sourceFromTo.dataVar != null &&
                                targetFromTo.dataVar != null)
                        {
                                boolean extendedPropInterpretation = true;
                                if (propQ instanceof PropertyVar) {
                                        extendedPropInterpretation = false;
                                }
                                DataPathSelector dps = new DataPathSelector(