Example usage for javax.xml.xpath XPathFactory newXPath

List of usage examples for javax.xml.xpath XPathFactory newXPath

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Introduction

In this page you can find the example usage for javax.xml.xpath XPathFactory newXPath.

Prototype

public abstract XPath newXPath();

Source Link

Document

Return a new XPath using the underlying object model determined when the XPathFactory was instantiated.

Usage

From source file:org.apache.airavata.gfac.core.GFacUtils.java

public static List<Element> getElementList(Document doc, String expression) throws XPathExpressionException {
    XPathFactory xPathFactory = XPathFactory.newInstance();
    XPath xPath = xPathFactory.newXPath();
    XPathExpression expr = xPath.compile(expression);
    NodeList nodeList = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);
    List<Element> elementList = new ArrayList<Element>();
    for (int i = 0; i < nodeList.getLength(); i++) {
        Node item = nodeList.item(i);
        if (item instanceof Element) {
            elementList.add((Element) item);
        }//from   www . j av a2s.co  m
    }
    return elementList;
}

From source file:org.apache.ode.bpel.compiler.v1.xpath10.jaxp.JaxpXPath10ExpressionCompilerImpl.java

/**
 * Verifies validity of a xpath expression.
 *///from w  w  w . j  a va2 s.c o  m
protected void doJaxpCompile(OXPath10Expression out, Expression source) throws CompilationException {
    String xpathStr;
    Node node = source.getExpression();
    if (node == null) {
        throw new IllegalStateException("XPath string and xpath node are both null");
    }

    xpathStr = node.getNodeValue();
    xpathStr = xpathStr.trim();
    if (xpathStr.length() == 0) {
        throw new CompilationException(__msgs.errXPathSyntax(xpathStr));
    }

    try {
        __log.debug("JAXP compile: xpath = " + xpathStr);
        // use default XPath implementation
        XPathFactory xpf = XPathFactory.newInstance();
        __log.debug("JAXP compile: XPathFactory impl = " + xpf.getClass());
        XPath xpath = xpf.newXPath();
        xpath.setXPathFunctionResolver(
                new JaxpFunctionResolver(_compilerContext, out, source.getNamespaceContext(), _bpelNsURI));
        xpath.setXPathVariableResolver(new JaxpVariableResolver(_compilerContext, out));
        xpath.setNamespaceContext(source.getNamespaceContext());
        XPathExpression xpe = xpath.compile(xpathStr);
        // dummy evaluation to resolve variables and functions (hopefully complete...)
        xpe.evaluate(DOMUtils.newDocument());
        out.xpath = xpathStr;
    } catch (XPathExpressionException e) {
        throw new CompilationException(__msgs.errUnexpectedCompilationError(e.getMessage()), e);
    }
}

From source file:org.apache.ode.bpel.compiler.v1.xpath20.XPath20ExpressionCompilerImpl.java

private void doJaxpCompile(OXPath20ExpressionBPEL20 out, Expression source) throws CompilationException {
    String xpathStr;/*from w  w w  .java  2  s . c om*/
    Node node = source.getExpression();
    if (node == null) {
        throw new IllegalStateException("XPath string and xpath node are both null");
    }
    if (node.getNodeType() != Node.TEXT_NODE) {
        throw new CompilationException(__msgs.errUnexpectedNodeTypeForXPath(DOMUtils.domToString(node)));
    }
    xpathStr = node.getNodeValue();
    xpathStr = xpathStr.trim();
    if (xpathStr.length() == 0) {
        throw new CompilationException(__msgs.warnXPath20Syntax(DOMUtils.domToString(node), "empty string"));
    }

    out.xpath = xpathStr;
    try {
        __log.debug("Compiling expression " + xpathStr);
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_SAXON,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        XPathFactory xpf = XPathFactory.newInstance(NamespaceConstant.OBJECT_MODEL_SAXON);
        JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(_compilerContext, out,
                source.getNamespaceContext(), _bpelNS);
        JaxpVariableResolver varResolver = new JaxpVariableResolver(_compilerContext, out);
        XPath xpe = xpf.newXPath();
        xpe.setXPathFunctionResolver(funcResolver);
        xpe.setXPathVariableResolver(varResolver);
        xpe.setNamespaceContext(source.getNamespaceContext());
        XPathExpression expr = xpe.compile(xpathStr);
        // evaluate the expression so as to initialize the variables
        try {
            expr.evaluate(node);
        } catch (XPathExpressionException xpee) {
            // swallow errors caused by uninitialized variable 
        }
        for (String varExpr : extractVariableExprs(xpathStr)) {
            expr = xpe.compile(varExpr);
            try {
                expr.evaluate(node);
            } catch (XPathExpressionException xpee) {
                // swallow errors caused by uninitialized variable 
            }
        }
    } catch (XPathFactoryConfigurationException xpfce) {
        __log.debug(xpfce);
        __log.info("Couldn't validate properly expression " + xpathStr);
    } catch (XPathExpressionException e) {
        __log.debug(e);
        __log.info("Couldn't validate properly expression " + xpathStr);
    } catch (WrappedResolverException wre) {
        if (wre._compilationMsg != null)
            throw new CompilationException(wre._compilationMsg, wre);
        if (wre.getCause() instanceof CompilationException)
            throw (CompilationException) wre.getCause();
        throw wre;
    }
}

From source file:org.apache.ode.bpel.elang.xpath20.compiler.XPath20ExpressionCompilerImpl.java

private void doJaxpCompile(OXPath20ExpressionBPEL20 out, Expression source) throws CompilationException {
    String xpathStr;// w ww .  ja v  a2s.  c o  m
    Node node = source.getExpression();
    if (node == null) {
        throw new CompilationException(__msgs.errEmptyExpression(source.getURI(),
                new QName(source.getElement().getNamespaceURI(), source.getElement().getNodeName())));
    }
    if (node.getNodeType() != Node.TEXT_NODE && node.getNodeType() != Node.CDATA_SECTION_NODE) {
        throw new CompilationException(__msgs.errUnexpectedNodeTypeForXPath(DOMUtils.domToString(node)));
    }
    xpathStr = node.getNodeValue();
    xpathStr = xpathStr.trim();
    if (xpathStr.length() == 0) {
        throw new CompilationException(__msgs.warnXPath20Syntax(DOMUtils.domToString(node), "empty string"));
    }

    out.xpath = xpathStr;
    try {
        __log.debug("Compiling expression " + xpathStr);
        XPathFactory xpf = new XPathFactoryImpl();
        JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(_compilerContext, out,
                source.getNamespaceContext(), _bpelNS);
        JaxpVariableResolver varResolver = new JaxpVariableResolver(_compilerContext, out);
        XPath xpe = xpf.newXPath();
        xpe.setXPathFunctionResolver(funcResolver);
        xpe.setXPathVariableResolver(varResolver);
        xpe.setNamespaceContext(source.getNamespaceContext());
        XPathExpression expr = xpe.compile(xpathStr);
        // evaluate the expression so as to initialize the variables
        try {
            expr.evaluate(node);
        } catch (XPathExpressionException xpee) {
            // swallow errors caused by uninitialized variable
        }
        for (String varExpr : extractVariableExprs(xpathStr)) {
            expr = xpe.compile(varExpr);
            try {
                expr.evaluate(node);
            } catch (XPathExpressionException xpee) {
                // swallow errors caused by uninitialized variable
            }
        }
        for (String functionExpr : extractFunctionExprs(xpathStr)) {
            expr = xpe.compile(functionExpr);
            try {
                expr.evaluate(node);
            } catch (XPathExpressionException xpee) {
                // swallow errors caused by uninitialized variable
            }
        }
    } catch (XPathExpressionException e) {
        __log.debug(e);
        __log.info("Couldn't validate properly expression " + xpathStr);
    } catch (WrappedResolverException wre) {
        if (wre._compilationMsg != null)
            throw new CompilationException(wre._compilationMsg, wre);
        if (wre.getCause() instanceof CompilationException)
            throw (CompilationException) wre.getCause();
        throw wre;
    }
}

From source file:org.apache.ode.bpel.rtrep.v1.xpath10.jaxp.JaxpXPath10ExpressionRuntime.java

private Object evaluate(OExpression cexp, EvaluationContext ctx, QName type) throws FaultException {
    try {/*from  w w w  .ja  v a2  s. c  o m*/
        OXPath10Expression oxpath = (OXPath10Expression) cexp;
        __log.debug("JAXP runtime: evaluating " + oxpath.xpath);
        // use default XPath implementation
        XPathFactory xpf = XPathFactory.newInstance();
        __log.debug("JAXP runtime: XPathFactory impl = " + xpf.getClass());
        XPath xpe = xpf.newXPath();
        xpe.setXPathFunctionResolver(new JaxpFunctionResolver(ctx, oxpath));
        xpe.setXPathVariableResolver(new JaxpVariableResolver(ctx, oxpath));
        xpe.setNamespaceContext(oxpath.namespaceCtx);
        XPathExpression expr = xpe.compile(((OXPath10Expression) cexp).xpath);
        Object evalResult = expr
                .evaluate(ctx.getRootNode() == null ? DOMUtils.newDocument() : ctx.getRootNode(), type);
        if (evalResult != null && __log.isDebugEnabled()) {
            __log.debug("Expression " + cexp.toString() + " generated result " + evalResult + " - type="
                    + evalResult.getClass().getName());
            if (ctx.getRootNode() != null)
                __log.debug("Was using context node " + DOMUtils.domToString(ctx.getRootNode()));
        }
        return evalResult;
    } catch (XPathExpressionException e) {
        // Extracting the real cause from all this wrapping isn't a simple task
        Throwable cause = e.getCause() != null ? e.getCause() : e;
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, cause.getMessage(),
                cause);
    } catch (WrappedFaultException wre) {
        __log.debug("Could not evaluate expression because of ", wre);
        throw (FaultException) wre.getCause();
    } catch (Throwable t) {
        __log.debug("Could not evaluate expression because of ", t);
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, t.getMessage(), t);
    }

}

From source file:org.apache.ode.bpel.rtrep.v1.xpath20.XPath20ExpressionRuntime.java

private Object evaluate(OExpression cexp, EvaluationContext ctx, QName type) throws FaultException {
    try {/*  w  w  w.ja  v  a  2s . co  m*/
        OXPath20ExpressionBPEL20 oxpath20 = ((OXPath20ExpressionBPEL20) cexp);
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_SAXON,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        // JAXP based XPath 1.0 runtime does not work anymore after a XPath 2.0 has been evaluated if this is set.
        // System.setProperty("javax.xml.xpath.XPathFactory:"+XPathConstants.DOM_OBJECT_MODEL,
        //        "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_JDOM,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_XOM,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_DOM4J,
                "net.sf.saxon.xpath.XPathFactoryImpl");

        XPathFactory xpf = XPathFactory.newInstance(NamespaceConstant.OBJECT_MODEL_SAXON);
        JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(ctx, oxpath20);
        JaxpVariableResolver varResolver = new JaxpVariableResolver(ctx, oxpath20,
                ((XPathFactoryImpl) xpf).getConfiguration());
        xpf.setXPathFunctionResolver(funcResolver);
        xpf.setXPathVariableResolver(varResolver);
        XPath xpe = xpf.newXPath();
        xpe.setNamespaceContext(oxpath20.namespaceCtx);
        XPathExpression expr = xpe.compile(((OXPath10Expression) cexp).xpath);
        Node contextNode = ctx.getRootNode() == null ? DOMUtils.newDocument() : ctx.getRootNode();
        Object evalResult = expr.evaluate(contextNode, type);
        if (evalResult != null && __log.isDebugEnabled()) {
            __log.debug("Expression " + cexp.toString() + " generated result " + evalResult + " - type="
                    + evalResult.getClass().getName());
            if (ctx.getRootNode() != null)
                __log.debug("Was using context node " + DOMUtils.domToString(ctx.getRootNode()));
        }
        return evalResult;
    } catch (XPathExpressionException e) {
        // Extracting the real cause from all this wrapping isn't a simple task
        Throwable cause = e.getCause() != null ? e.getCause() : e;
        if (cause instanceof DynamicError) {
            Throwable th = ((DynamicError) cause).getException();
            if (th != null) {
                cause = th;
                if (cause.getCause() != null)
                    cause = cause.getCause();
            }
        }
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, cause.getMessage(),
                cause);
    } catch (WrappedFaultException wre) {
        __log.debug("Could not evaluate expression because of ", wre);
        throw (FaultException) wre.getCause();
    } catch (Throwable t) {
        __log.debug("Could not evaluate expression because of ", t);
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, t.getMessage(), t);
    }
}

From source file:org.apache.ode.bpel.rtrep.v2.xpath20.XPath20ExpressionRuntime.java

private Object evaluate(OExpression cexp, EvaluationContext ctx, QName type) throws FaultException {
    try {//from  w  w  w .  j a  v a  2  s  . com
        OXPath20ExpressionBPEL20 oxpath20 = ((OXPath20ExpressionBPEL20) cexp);
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_SAXON,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        // JAXP based XPath 1.0 runtime does not work anymore after a XPath 2.0 has been evaluated if this is set.
        // System.setProperty("javax.xml.xpath.XPathFactory:"+XPathConstants.DOM_OBJECT_MODEL,
        //        "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_JDOM,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_XOM,
                "net.sf.saxon.xpath.XPathFactoryImpl");
        System.setProperty("javax.xml.xpath.XPathFactory:" + NamespaceConstant.OBJECT_MODEL_DOM4J,
                "net.sf.saxon.xpath.XPathFactoryImpl");

        XPathFactory xpf = XPathFactory.newInstance(NamespaceConstant.OBJECT_MODEL_SAXON);
        JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(ctx, oxpath20);
        JaxpVariableResolver varResolver = new JaxpVariableResolver(ctx, oxpath20,
                ((XPathFactoryImpl) xpf).getConfiguration());
        xpf.setXPathFunctionResolver(funcResolver);
        xpf.setXPathVariableResolver(varResolver);
        XPath xpe = xpf.newXPath();
        xpe.setNamespaceContext(oxpath20.namespaceCtx);
        XPathExpression expr = xpe.compile(((OXPath10Expression) cexp).xpath);
        Node contextNode = ctx.getRootNode() == null ? DOMUtils.newDocument() : ctx.getRootNode();
        // Create step nodes in XPath in case it is incompletely instantiated 
        if (oxpath20.insertMissingData) {
            XPath20ExpressionModifier modifier = new XPath20ExpressionModifier(oxpath20.namespaceCtx,
                    ((XPathFactoryImpl) xpf).getConfiguration().getNamePool());
            Node temp = ctx.getRootNode();
            if (temp.getLocalName().equals("message") && temp.getNamespaceURI() == null
                    && temp.getFirstChild() != null && temp.getFirstChild().getFirstChild() != null) {
                modifier.insertMissingData(expr, temp.getFirstChild().getFirstChild());
            } else {
                modifier.insertMissingData(expr, temp);
            }
        }

        Object evalResult = expr.evaluate(contextNode, type);
        if (evalResult != null && __log.isDebugEnabled()) {
            __log.debug("Expression " + cexp.toString() + " generated result " + evalResult + " - type="
                    + evalResult.getClass().getName());
            if (ctx.getRootNode() != null)
                __log.debug("Was using context node " + DOMUtils.domToString(ctx.getRootNode()));
        }
        return evalResult;
    } catch (XPathExpressionException e) {
        // Extracting the real cause from all this wrapping isn't a simple task
        Throwable cause = e.getCause() != null ? e.getCause() : e;
        if (cause instanceof DynamicError) {
            Throwable th = ((DynamicError) cause).getException();
            if (th != null) {
                cause = th;
                if (cause.getCause() != null)
                    cause = cause.getCause();
            }
        }
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, cause.getMessage(),
                cause);
    } catch (WrappedFaultException wre) {
        __log.debug("Could not evaluate expression because of ", wre);
        throw (FaultException) wre.getCause();
    } catch (Throwable t) {
        __log.debug("Could not evaluate expression because of ", t);
        throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, t.getMessage(), t);
    }

}

From source file:org.apache.syncope.console.commons.XMLRolesReader.java

/**
 * Get all roles allowed for specific page and action requested.
 *
 * @param pageId/*  ww w .j a v  a 2s  .c o  m*/
 * @param actionId
 * @return roles list comma separated
 */
public String getAllAllowedRoles(final String pageId, final String actionId) {
    if (doc == null) {
        return StringUtils.EMPTY;
    }

    final StringBuilder roles = new StringBuilder();
    try {
        XPathFactory factory = XPathFactory.newInstance();
        XPath xpath = factory.newXPath();
        XPathExpression expr = xpath.compile(
                "//page[@id='" + pageId + "']/" + "action[@id='" + actionId + "']/" + "entitlement/text()");
        Object result = expr.evaluate(doc, XPathConstants.NODESET);

        NodeList nodes = (NodeList) result;

        for (int i = 0; i < nodes.getLength(); i++) {
            if (i > 0) {
                roles.append(",");
            }
            roles.append(nodes.item(i).getNodeValue());
        }
    } catch (XPathExpressionException e) {
        LOG.error("While parsing authorizations file", e);
    }

    LOG.debug("Authorizations found: {}", roles);

    return roles.toString();
}

From source file:org.apereo.portal.layout.dlm.PositionManager.java

/**
 * Return true if the passed in node or any downstream (higher index)
 * siblings <strong>relative to its destination location</strong> have
 * moveAllowed="false"./*from w  w w  .  j a  v a 2s  .  c  o  m*/
 */
private static boolean isNotReparentable(NodeInfo ni, Element compViewParent, Element positionSet) {

    // This one is easy -- can't re-parent a node with dlm:moveAllowed=false
    if (ni.getNode().getAttribute(Constants.ATT_MOVE_ALLOWED).equals("false")) {
        return true;
    }

    try {
        /*
         *  Annoying to do in Java, but we need to find our own placeholder
         *  element in the positionSet
         */
        final XPathFactory xpathFactory = XPathFactory.newInstance();
        final XPath xpath = xpathFactory.newXPath();
        final String findPlaceholderXpath = ".//*[local-name()='position' and @name='" + ni.getId() + "']";
        final XPathExpression findPlaceholder = xpath.compile(findPlaceholderXpath);
        final NodeList findPlaceholderList = (NodeList) findPlaceholder.evaluate(positionSet,
                XPathConstants.NODESET);
        switch (findPlaceholderList.getLength()) {
        case 0:
            LOG.warn("Node not found for XPathExpression=\"" + findPlaceholderXpath + "\" in positionSet="
                    + XmlUtilitiesImpl.toString(positionSet));
            return true;
        case 1:
            // This is healthy
            break;
        default:
            LOG.warn("More than one node found for XPathExpression=\"" + findPlaceholderXpath
                    + "\" in positionSet=" + XmlUtilitiesImpl.toString(positionSet));
            return true;
        }
        final Element placeholder = (Element) findPlaceholderList.item(0); // At last

        for (Element nextPlaceholder = (Element) placeholder.getNextSibling(); // Start with the next dlm:position element after placeholder
                nextPlaceholder != null; // As long as we have a placeholder to look at
                nextPlaceholder = (Element) nextPlaceholder.getNextSibling()) { // Advance to the next placeholder

            if (LOG.isDebugEnabled()) {
                LOG.debug("Considering whether node ''" + ni.getId()
                        + "' is Reparentable;  subsequent sibling is:  "
                        + nextPlaceholder.getAttribute("name"));
            }

            /*
             * Next task:  we have to find the non-placeholder representation of
             * the nextSiblingPlaceholder within the compViewParent
             */
            final String unmaskPlaceholderXpath = ".//*[@ID='" + nextPlaceholder.getAttribute("name") + "']";
            final XPathExpression unmaskPlaceholder = xpath.compile(unmaskPlaceholderXpath);
            final NodeList unmaskPlaceholderList = (NodeList) unmaskPlaceholder.evaluate(compViewParent,
                    XPathConstants.NODESET);
            switch (unmaskPlaceholderList.getLength()) {
            case 0:
                // Not a problem;  the nextSiblingPlaceholder also refers
                // to a node that has been moved to this context (afaik)
                continue;
            case 1:
                final Element nextSibling = (Element) unmaskPlaceholderList.item(0);
                if (LOG.isDebugEnabled()) {
                    LOG.debug("Considering whether node ''" + ni.getId()
                            + "' is Reparentable;  subsequent sibling '" + nextSibling.getAttribute("ID")
                            + "' has dlm:moveAllowed="
                            + !nextSibling.getAttribute(Constants.ATT_MOVE_ALLOWED).equals("false"));
                }

                // Need to perform some checks...
                if (nextSibling.getAttribute(Constants.ATT_MOVE_ALLOWED).equals("false")) {

                    /*
                     *  The following check is a bit strange;  it seems to verify
                     *  that the current NodeInfo and the nextSibling come from the
                     *  same fragment.  If they don't, the re-parenting is allowable.
                     *  I believe this check could only be unsatisfied in the case
                     *  of tabs.
                     */
                    Precedence p = Precedence.newInstance(nextSibling.getAttribute(Constants.ATT_FRAGMENT));
                    if (ni.getPrecedence().isEqualTo(p)) {
                        return true;
                    }
                }
                break;
            default:
                LOG.warn("More than one node found for XPathExpression=\"" + unmaskPlaceholderXpath
                        + "\" in compViewParent");
                return true;
            }
        }
    } catch (XPathExpressionException xpe) {
        throw new RuntimeException("Failed to evaluate XPATH", xpe);
    }

    return false; // Re-parenting is "not disallowed" (double-negative less readable)

}

From source file:org.apereo.portal.layout.dlm.remoting.UpdatePreferencesServlet.java

/**
 * Subscribe a user to a pre-formatted tab (pulled DLM fragment).
 *
 * @param request//w w  w  . j  av  a  2 s.c  o  m
 * @param response
 * @return
 * @throws IOException
 */
@RequestMapping(method = RequestMethod.POST, params = "action=subscribeToTab")
public ModelAndView subscribeToTab(HttpServletRequest request, HttpServletResponse response)
        throws IOException {

    IUserInstance ui = userInstanceManager.getUserInstance(request);
    IPerson per = getPerson(ui, response);

    UserPreferencesManager upm = (UserPreferencesManager) ui.getPreferencesManager();
    IUserLayoutManager ulm = upm.getUserLayoutManager();

    // Get the fragment owner's name from the request and construct
    // an IPerson object representing that user
    String fragmentOwnerName = request.getParameter("sourceID");
    if (StringUtils.isBlank(fragmentOwnerName)) {
        logger.warn("Attempted to subscribe to tab with null owner ID");
        response.sendError(HttpServletResponse.SC_BAD_REQUEST);
        return new ModelAndView("jsonView",
                Collections.singletonMap("error", "Attempted to subscribe to tab with null owner ID"));
    }
    RestrictedPerson fragmentOwner = PersonFactory.createRestrictedPerson();
    fragmentOwner.setUserName(fragmentOwnerName);

    // Mark the currently-authenticated user as subscribed to this fragment.
    // If an inactivated fragment registration already exists, update it
    // as an active subscription.  Otherwise, create a new fragment
    // subscription.
    IUserFragmentSubscription userFragmentInfo = userFragmentInfoDao.getUserFragmentInfo(per, fragmentOwner);
    if (userFragmentInfo == null) {
        userFragmentInfo = userFragmentInfoDao.createUserFragmentInfo(per, fragmentOwner);
    } else {
        userFragmentInfo.setActive(true);
        userFragmentInfoDao.updateUserFragmentInfo(userFragmentInfo);
    }

    try {
        // reload user layout and stylesheet to incorporate new DLM fragment
        ulm.loadUserLayout(true);

        // get the target node this new tab should be moved after
        String destinationId = request.getParameter("elementID");

        // get the user layout for the currently-authenticated user
        int uid = userIdentityStore.getPortalUID(fragmentOwner, false);
        final DistributedUserLayout userLayout = userLayoutStore.getUserLayout(per, upm.getUserProfile());
        Document layoutDocument = userLayout.getLayout();

        // attempt to find the new subscribed tab in the layout so we can
        // move it
        StringBuilder expression = new StringBuilder("//folder[@type='root']/folder[starts-with(@ID,'")
                .append(Constants.FRAGMENT_ID_USER_PREFIX).append(uid).append("')]");
        XPathFactory fac = XPathFactory.newInstance();
        XPath xpath = fac.newXPath();
        NodeList nodes = (NodeList) xpath.evaluate(expression.toString(), layoutDocument,
                XPathConstants.NODESET);
        String sourceId = nodes.item(0).getAttributes().getNamedItem("ID").getTextContent();
        ulm.moveNode(sourceId, ulm.getParentId(destinationId), destinationId);

        ulm.saveUserLayout();

        return new ModelAndView("jsonView", Collections.singletonMap("tabId", sourceId));

    } catch (XPathExpressionException e) {
        response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        return new ModelAndView("jsonView", Collections.singletonMap("error", "Xpath error"));
    } catch (PortalException e) {
        return handlePersistError(request, response, e);
    }

}