NullBlobStore.java

/**
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 *  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 General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.geowebcache.storage.blobstore.memory;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.log4j.Logger;
import org.geowebcache.storage.BlobStore;
import org.geowebcache.storage.BlobStoreListener;
import org.geowebcache.storage.StorageException;
import org.geowebcache.storage.TileObject;
import org.geowebcache.storage.TileRange;

/**
 * This class is an implementation of the {@link BlobStore} interface which does not store anything on the file system and can be used for doing a
 * pure in memory caching of the {@link TileObject}s. This class simply stores the layer metadata in a {@link Map} object. The
 * other operations are not executed.
 * 
 * @author Nicola Lagomarsini Geosolutions
 */
public class NullBlobStore implements BlobStore {

    private Map<String, Properties> metadataMap;

    /** {@link Logger} object used for logging exceptions */
    private final static Log LOGGER = LogFactory.getLog(NullBlobStore.class);

    public NullBlobStore() {
        // Map initialization
        metadataMap = new HashMap<String, Properties>();
    }

    @Override
    public boolean delete(String layerName) throws StorageException {
        return true;
    }

    @Override
    public boolean deleteByGridsetId(String layerName, String gridSetId) throws StorageException {
        return true;
    }

    @Override
    public boolean delete(TileObject obj) throws StorageException {
        return true;
    }

    @Override
    public boolean delete(TileRange obj) throws StorageException {
        return true;
    }

    @Override
    public boolean get(TileObject obj) throws StorageException {
        return false;
    }

    @Override
    public void put(TileObject obj) throws StorageException {
    }

    @Override
    public void clear() throws StorageException {
    }

    @Override
    public synchronized void destroy() {
        // Clear the properties map
        metadataMap.clear();
    }

    @Override
    public void addListener(BlobStoreListener listener) {
    }

    @Override
    public boolean removeListener(BlobStoreListener listener) {
        return true;
    }

    @Override
    public boolean rename(String oldLayerName, String newLayerName) throws StorageException {
        return true;
    }

    @Override
    public synchronized String getLayerMetadata(String layerName, String key) {
        // Check if the property is present
        Properties properties = metadataMap.get(layerName);
        if (properties != null) {
            // Returns the property associated to the key
            try {
                return URLDecoder.decode((String) properties.get(key), "UTF-8");
            } catch (UnsupportedEncodingException e) {
                LOGGER.error(e.getLocalizedMessage(), e);
            }
        }
        return null;
    }

    @Override
    public synchronized void putLayerMetadata(String layerName, String key, String value) {
        // Check if the property is present
        Properties props = metadataMap.get(layerName);
        if (props != null) {
            try {
                // If present adds the new property
                props.setProperty(key, URLEncoder.encode(value, "UTF-8"));
            } catch (UnsupportedEncodingException e) {
                LOGGER.error(e.getLocalizedMessage(), e);
            }
        } else {
            // Else creates a new Property object and them adds the new property
            props = new Properties();
            try {
                props.setProperty(key, URLEncoder.encode(value, "UTF-8"));
            } catch (UnsupportedEncodingException e) {
                LOGGER.error(e.getLocalizedMessage(), e);
            }
            metadataMap.put(layerName, props);
        }
    }
    
    @Override
    public boolean layerExists(String layerName) {
        return false;
    }
    
    @Override
    public boolean deleteByParametersId(String layerName, String parametersId)
            throws StorageException {
        return true;
    }

    @Override
    public Set<Map<String, String>> getParameters(String layerName) {
        return Collections.emptySet();
    }

    public Map<String,Optional<Map<String, String>>> getParametersMapping(String layerName) {
        return Collections.emptyMap();
    }
}