org.pentaho.reporting.engine.classic.extensions.datasources.mondrian.SchemaResolver.java Source code

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Here is the source code for org.pentaho.reporting.engine.classic.extensions.datasources.mondrian.SchemaResolver.java

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/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* Copyright (c) 2002-2017 Hitachi Vantara..  All rights reserved.
*/

package org.pentaho.reporting.engine.classic.extensions.datasources.mondrian;

import mondrian.olap.Util;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemException;
import org.apache.commons.vfs2.FileSystemManager;
import org.apache.commons.vfs2.VFS;
import org.pentaho.reporting.libraries.resourceloader.ResourceKey;
import org.pentaho.reporting.libraries.resourceloader.ResourceManager;

import java.io.File;
import java.io.IOException;

/**
 * This class emulates Mondrian's schema resolving and allows us to find a string that correctly represents a valid VFS
 * path for use in mondrian.
 *
 * @author Thomas Morgner.
 */
public class SchemaResolver {
    private static final Log logger = LogFactory.getLog(SchemaResolver.class);

    private SchemaResolver() {
    }

    public static String resolveSchema(final ResourceManager resourceManager, final ResourceKey contextKey,
            String catalogUrl) throws FileSystemException {
        final FileSystemManager fsManager = VFS.getManager();
        if (fsManager == null) {
            throw Util.newError("Cannot get virtual file system manager");
        }

        // Workaround VFS bug.
        if (catalogUrl.startsWith("file://localhost")) {
            catalogUrl = catalogUrl.substring("file://localhost".length());
        }
        if (catalogUrl.startsWith("file:")) {
            catalogUrl = catalogUrl.substring("file:".length());
        }

        try {
            final File catalogFile = new File(catalogUrl).getCanonicalFile();
            final FileObject file = fsManager.toFileObject(catalogFile);
            if (file.isReadable()) {
                return catalogFile.getPath();
            }
        } catch (FileSystemException fse) {
            logger.info("Failed to resolve schema file '" + catalogUrl
                    + "' as local file. Treating file as non-readable.", fse);
        } catch (IOException e) {
            logger.info("Failed to resolve schema file '" + catalogUrl
                    + "' as local file. Treating file as non-readable.", e);
        }

        if (contextKey == null) {
            return catalogUrl;
        }

        final File contextAsFile = getContextAsFile(contextKey);
        if (contextAsFile == null) {
            return catalogUrl;
        }

        final File resolvedFile = new File(contextAsFile.getParentFile(), catalogUrl);
        if (resolvedFile.isFile() && resolvedFile.canRead()) {
            return resolvedFile.getAbsolutePath();
        }

        return catalogUrl;
    }

    private static File getContextAsFile(ResourceKey key) {
        while (key != null) {
            final Object identifier = key.getIdentifier();
            if (identifier instanceof File) {
                return (File) identifier;
            }

            key = key.getParent();
        }
        return null;
    }

}