Examples with LockedDocument org.exist.dom.persistent.LockedDocument used on opensource projects

Example 91 with LockedDocument

use of org.exist.dom.persistent.LockedDocument in project exist by eXist-db.

the class XMLDBSetMimeType method eval.

@Override
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
    // Get handle to Mime-type info
    final MimeTable mimeTable = MimeTable.getInstance();
    // Get first parameter
    final String pathParameter = new AnyURIValue(args[0].itemAt(0).getStringValue()).toString();
    if (pathParameter.matches("^[a-z]+://.*")) {
        throw new XPathException("Can not set mime-type for resources outside the database.");
    }
    XmldbURI pathUri = null;
    try {
        pathUri = XmldbURI.xmldbUriFor(pathParameter);
    } catch (final URISyntaxException ex) {
        logger.debug(ex.getMessage());
        throw new XPathException("Invalid path '" + pathParameter + "'");
    }
    // Verify mime-type input
    MimeType newMimeType = null;
    if (args[1].isEmpty()) {
        // No input, use default mimetype
        newMimeType = mimeTable.getContentTypeFor(pathParameter);
        if (newMimeType == null) {
            throw new XPathException("Unable to determine mimetype for '" + pathParameter + "'");
        }
    } else {
        // Mimetype is provided, check if valid
        newMimeType = mimeTable.getContentType(args[1].getStringValue());
        if (newMimeType == null) {
            throw new XPathException("mime-type '" + args[1].getStringValue() + "' is not supported.");
        }
    }
    // Get mime-type of resource
    MimeType currentMimeType = getMimeTypeStoredResource(pathUri);
    if (currentMimeType == null) {
        // stored resource has no mime-type (unexpected situation)
        // fall back to document name
        logger.debug("Resource '{}' has no mime-type, retrieve from document name.", pathUri);
        currentMimeType = mimeTable.getContentTypeFor(pathUri);
        // if extension based lookup still fails
        if (currentMimeType == null) {
            throw new XPathException("Unable to determine mime-type from path '" + pathUri + "'.");
        }
    }
    // in some cases value null is set, then allow to set to new value (repair action)
    if (newMimeType.isXMLType() != currentMimeType.isXMLType()) {
        throw new XPathException("New mime-type must be a " + currentMimeType.getXMLDBType() + " mime-type");
    }
    // At this moment it is possible to update the mimetype
    final DBBroker broker = context.getBroker();
    final BrokerPool brokerPool = broker.getBrokerPool();
    // relative collection Path: add the current base URI
    pathUri = context.getBaseURI().toXmldbURI().resolveCollectionPath(pathUri);
    try (final Txn txn = broker.continueOrBeginTransaction();
        final LockedDocument lockedDocument = broker.getXMLResource(pathUri, LockMode.WRITE_LOCK)) {
        // try to open the document and acquire a lock
        final DocumentImpl doc = lockedDocument == null ? null : lockedDocument.getDocument();
        if (doc == null) {
            // no document selected, abort
            txn.abort();
        } else {
            // set new mime-type
            doc.setMimeType(newMimeType.getName());
            // store meta data into database
            broker.storeMetadata(txn, doc);
            // commit changes
            txn.commit();
        }
    } catch (final Exception e) {
        logger.error(e.getMessage());
        throw new XPathException(this, e);
    }
    return Sequence.EMPTY_SEQUENCE;
}