unparser.java

jena2.5.4推理机系统的一种最基本实现 HP实验室出品

     */
    private boolean wPropertyEltResource(WType wt, Property prop, Statement s,
            RDFNode r) {
        if (prettyWriter.sParseTypeResourcePropertyElt)
            return false;
        if (r instanceof Literal)
            return false;
        Resource res = (Resource) r;
        if (!isGenuineAnon(res))
            return false;
        if (getType(res) != null)
            return false; // preferred typed node construction.
        // print out.
        done(s);
        tab();
        print("<");
        wt.wTypeStart(prop);
        indentPlus();
        wIdAttrReified(s);
        wParseResource();
        print(">");
        wPropertyEltStar(res);
        indentMinus();
        tab();
        print("</");
        wt.wTypeEnd(prop);
        print(">");
        return true;
    }

    /*
     * [6.12] propertyElt ::= '<' propName idAttr? '>' value '</' propName '>'
     */
    private boolean wPropertyEltValue(WType wt, Property prop, Statement s,
            RDFNode r) {
        return wPropertyEltValueString(wt, prop, s, r)
                || wPropertyEltValueObj(wt, prop, s, r);
    }

    /*
     * [6.12] propertyElt ::= '<' propName idAttr? '>' value '</' propName '>'
     */
    private boolean wPropertyEltValueString(WType wt, Property prop,
            Statement s, RDFNode r) {
        if (r instanceof Literal) {
            done(s);
            Literal lt = (Literal) r;
            String lang = lt.getLanguage();
            tab();
            print("<");
            wt.wTypeStart(prop);
            wIdAttrReified(s);
            maybeNewline();
            if (lang != null && lang.length() > 0)
                print(" xml:lang=" + q(lang));
            maybeNewline();
            print(">");
            wValueString(lt);
            print("</");
            wt.wTypeEnd(prop);
            print(">");
            return true;
        }
        return false;

    }

    /*
     * [6.17.2] value ::= string
     */
    private void wValueString(Literal lt) {
        String val = lt.getString();
        print(Util.substituteEntitiesInElementContent(val));
    }

    /*
     * [6.12] propertyElt ::= '<' propName idAttr? '>' value '</' propName '>'
     * [6.17.1] value ::= obj
     */
    private boolean wPropertyEltValueObj(WType wt, Property prop, Statement s,
            RDFNode r) {
        if (r instanceof Resource && !prettyWriter.sResourcePropertyElt) {
            Resource res = (Resource) r;
            done(s);
            tab();
            print("<");
            wt.wTypeStart(prop);
            wIdAttrReified(s);
            print(">");
            tab();
            indentPlus();
            wObj(res, false);
            indentMinus();
            tab();
            print("</");
            wt.wTypeEnd(prop);
            print(">");
            return true;
        }

        return false;

    }

    /*
     * [daml.1 - 6.12 cont.] | '<' propName idAttr? parseDamlCollection '>'
     * obj* '</' propName '>'
     */
    private boolean wPropertyEltDamlCollection(WType wt, Property prop,
            Statement s, RDFNode r) {
        boolean daml = true;
        Statement list[][] = getDamlList(r);
        if (list == null) {
            daml = false;
            list = getRDFList(r);
        }
        if (list == null)
            return false;
        // print out.
        done(s);
        // record all done's first - they may impact the
        // way we print the values.
        for (int i = 0; i < list.length; i++) {
            done(list[i][0]);
            done(list[i][1]);
            if (daml)
                done(list[i][2]);
        }
        tab();
        print("<");
        wt.wTypeStart(prop);
        indentPlus();
        wIdAttrReified(s);
        if (daml)
            wParseDamlCollection();
        else
            wParseCollection();

        print(">");
        for (int i = 0; i < list.length; i++) {
            wObj((Resource) list[i][0].getObject(), false);
        }
        indentMinus();
        tab();
        print("</");
        wt.wTypeEnd(prop);
        print(">");
        return true;
    }

    // propAttr* with no left over statements.
    private void wPropAttrAll(Resource r) {
        wPropAttrSome(r);
        if (hasProperties(r))
            error("Bad call to wPropAttrAll");
    }

    // propAttr* possibly with left over statements.
    private void wPropAttrSome(Resource r) {
        ClosableIterator ss = listProperties(r);
        try {
            Set seen = new HashSet();
            while (ss.hasNext()) {
                Statement s = (Statement) ss.next();
                if (canBeAttribute(s, seen)) {
                    done(s);
                    wPropAttr(s.getPredicate(), s.getObject());
                }
            }
        } finally {
            ss.close();
        }
    }

    /*
     * [6.2] obj ::= description | container [6.3] description ::= '<rdf:Description'
     * idAboutAttr? bagIdAttr? propAttr* '/>' | '<rdf:Description' idAboutAttr?
     * bagIdAttr? propAttr* '>' propertyElt* '</rdf:Description>' | typedNode
     * [6.4] container ::= sequence | bag | alternative We use: [6.2a] obj ::=
     * description | container | typedNode [6.3a] description ::= '<rdf:Description'
     * idAboutAttr? bagIdAttr? propAttr* '/>' | '<rdf:Description' idAboutAttr?
     * bagIdAttr? propAttr* '>' propertyElt* '</rdf:Description>'
     * 
     * This method has got somewhat messy. If we are not at the topLevel we may
     * choose to not expand a node but just use a typedNode ::= '<' typeName
     * idAboutAttr '/>' rule. This rules also applies to Bags that we feel
     * unconfortable with, such as a Bag arising from a BagId rule that we don't
     * handle properly.
     * 
     * 
     */
    private boolean wObj(Resource r, boolean topLevel) {
        try {
            doing.add(r);
            Statement typeStatement = getType(r);
            if (typeStatement != null) {
                Resource t = typeStatement.getResource();
                if (!topLevel) {
                    if (pleasingTypeSet.contains(t) && (!isGenuineAnon(r))) {
                        return wTypedNodeNoProperties(r);
                    }
                }
                return wTypedNode(r) || wDescription(r);
            }
            return wDescription(r);
        } finally {
            doing.remove(r);
        }
    }

    abstract private class WType {
        abstract void wTypeStart(Resource uri);

        abstract void wTypeEnd(Resource uri);
    }

    static private int RDF_HASH = RDF.getURI().length();

    private WType wdesc = new WType() {
        void wTypeStart(Resource u) {
            print(prettyWriter.rdfEl(u.getURI().substring(RDF_HASH)));
        }

        void wTypeEnd(Resource u) {
            print(prettyWriter.rdfEl(u.getURI().substring(RDF_HASH)));
        }
    };

    private WType wtype = new WType() {
        void wTypeStart(Resource u) {
            print(prettyWriter.startElementTag(u.getURI()));
        }

        void wTypeEnd(Resource u) {
            print(prettyWriter.endElementTag(u.getURI()));
        }
    };

    /*
     * [6.3a] description ::= '<rdf:Description' idAboutAttr? bagIdAttr?
     * propAttr* '/>' | '<rdf:Description' idAboutAttr? bagIdAttr? propAttr*
     * '>' propertyElt* '</rdf:Description>'
     */
    private boolean wDescription(Resource r) {
        return wTypedNodeOrDescription(wdesc, DESCRIPTION, r);
    }

    /*
     * [6.13] typedNode ::= '<' typeName idAboutAttr? bagIdAttr? propAttr* '/>' | '<'
     * typeName idAboutAttr? bagIdAttr? propAttr* '>' propertyElt* '</'
     * typeName '>'
     */
    private boolean wTypedNode(Resource r) {
        Statement st = getType(r);
        if (st == null)
            return false;
        Resource type = st.getResource();
        done(st);
        return wTypedNodeOrDescription(wtype, type, r);
    }

    private boolean wTypedNodeOrDescription(WType wt, Resource ty, Resource r) {
        // preparation - look for the li's.
        Vector found = new Vector();
        ClosableIterator ss = listProperties(r);
        try {
            int greatest = 0;
            if (!prettyWriter.sListExpand)
                while (ss.hasNext()) {
                    Statement s = (Statement) ss.next();
                    int ix = s.getPredicate().getOrdinal();
                    if (ix != 0) {
                        if (ix > greatest) {
                            found.setSize(ix);
                            greatest = ix;
                        }
                        found.set(ix - 1, s);
                    }
                }
        } finally {
            ss.close();
        }
        int last = found.indexOf(null);
        List li = last == -1 ? found : found.subList(0, last);

        return wTypedNodeOrDescriptionCompact(wt, ty, r, li)
                || wTypedNodeOrDescriptionLong(wt, ty, r, li);
    }

    /*
     * [6.13.1] typedNode ::= '<' typeName idAboutAttr? bagIdAttr? propAttr*
     * '/>'
     */
    private boolean wTypedNodeOrDescriptionCompact(WType wt, Resource ty,
            Resource r, List li) {
        // Conditions
        if ((!li.isEmpty()) || !allPropsAreAttr(r))
            return false;
        // Write out
        tab();
        print("<");
        wt.wTypeStart(ty);
        indentPlus();
        wIdAboutAttrOpt(r);
        wPropAttrAll(r);
        print("/>");
        indentMinus();
        return true;
    }

    /*
     * [6.13.1] typedNode ::= '<' typeName idAboutAttr '/>'
     */
    private boolean wTypedNodeNoProperties(Resource r) {
        // Conditions
        if (isGenuineAnon(r))
            return false;
        Statement st = getType(r);
        if (st == null)
            return false;
        Resource type = st.getResource();
        done(st);
        // Write out
        tab();
        print("<");
        wtype.wTypeStart(type);
        indentPlus();
        // if (hasProperties(r))
        // wAboutAttr(r);
        // else
        wIdAboutAttrOpt(r);
        print("/>");
        indentMinus();
        return true;
    }

    /*
     * [6.13.2] typedNode ::= '<' typeName idAboutAttr? bagIdAttr? propAttr*
     * '>' propertyElt* '</' typeName '>'
     */
    private boolean wTypedNodeOrDescriptionLong(WType wt, Resource ty,
            Resource r, List li) {
        Iterator it = li.iterator();
        while (it.hasNext()) {
            done((Statement) it.next());
        }

        tab();
        print("<");
        wt.wTypeStart(ty);
        indentPlus();
        wIdAboutAttrOpt(r);
        wPropAttrSome(r);
        print(">");
        wLiEltStar(li.iterator());
        wPropertyEltStar(r);
        indentMinus();
        tab();
        print("</");
        wt.wTypeEnd(ty);
        print(">");
        return true;
    }

    private void wPropertyEltStar(Resource r) {
        ClosableIterator ss = this.listProperties(r);
        try {
            while (ss.hasNext()) {
                Statement s = (Statement) ss.next();
                wPropertyElt(wtype, s.getPredicate(), s, s.getObject());
            }
        } finally {
            ss.close();
        }
    }

    private void wLiEltStar(Iterator ss) {
        while (ss.hasNext()) {
            Statement s = (Statement) ss.next();
            wPropertyElt(wdesc, LI, s, s.getObject());
        }
    }

    /*
     * [6.5] idAboutAttr ::= idAttr | aboutAttr | aboutEachAttr we use [6.5a]
     * idAboutAttr ::= idAttr | aboutAttr
     */
    private Set idDone = new HashSet();

    private boolean wIdAboutAttrOpt(Resource r) {
        return wIdAttrOpt(r) || wNodeIDAttr(r) || wAboutAttr(r);
    }

    /**
     * Returns false if the resource is not genuinely anonymous and cannot be
     * referred to using an ID. [6.6] idAttr ::= ' ID="' IDsymbol '"'
     */
    private boolean wIdAttrOpt(Resource r) {

        if (isGenuineAnon(r))
            return true; // We have output resource (with nothing).
        if (prettyWriter.sIdAttr)
            return false;
        if (r.isAnon())
            return false;
        if (isLocalReference(r)) {
            // Try and use the reification rules if they apply.
            // Issue: aren't we just about to list those statements explicitly.
            if (wantReification(r))
                return false;
            // Can be an ID if not already output.
            if (idDone.contains(r)) {
                return false; // We have already output this one.
            }

            idDone.add(r);
            print(" ");
            printRdfAt("ID");
            print("=");
            print(quote(getLocalName(r)));
            return true;

        }
        return false;

    }

    /*
     * [6.7] aboutAttr ::= ' about="' URI-reference '"'
     */
    private boolean wAboutAttr(Resource r) {
        print(" ");