org.codice.ddf.endpoints.rest.action.ActionProviderRegistryProxy.java Source code

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Here is the source code for org.codice.ddf.endpoints.rest.action.ActionProviderRegistryProxy.java

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/**
 * Copyright (c) Codice Foundation
 * <p/>
 * This 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 any later version.
 * <p/>
 * 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. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package org.codice.ddf.endpoints.rest.action;

import java.util.Dictionary;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.osgi.framework.BundleContext;
import org.osgi.framework.FrameworkUtil;
import org.osgi.framework.ServiceReference;
import org.osgi.framework.ServiceRegistration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import ddf.action.ActionProvider;
import ddf.catalog.Constants;
import ddf.catalog.transform.MetacardTransformer;
import ddf.catalog.transformer.attribute.AttributeMetacardTransformer;

/**
 * Registers {@link ActionProvider} objects into the Service Registry based upon the services
 * provided by other objects.
 *
 * @author Ashraf Barakat
 * @author ddf.isgs@lmco.com
 */
public class ActionProviderRegistryProxy {

    static final String ACTION_ID_PREFIX = "catalog.data.metacard.";

    private static final String PROVIDER_INTERFACE_NAME = ActionProvider.class.getName();

    private static final Logger LOGGER = LoggerFactory.getLogger(ActionProviderRegistryProxy.class);

    private Map<ServiceReference<MetacardTransformer>, ServiceRegistration> actionProviderRegistry = new HashMap<>();

    private MetacardTransformerActionProviderFactory actionFactory;

    public ActionProviderRegistryProxy(MetacardTransformerActionProviderFactory actionFactory) {
        this.actionFactory = actionFactory;
    }

    public void bind(ServiceReference<MetacardTransformer> reference) {

        LOGGER.info("New service registered [{}]", reference);

        String transformerId = null;

        if (reference.getProperty(Constants.SERVICE_ID) != null) {

            transformerId = reference.getProperty(Constants.SERVICE_ID).toString();

            // backwards compatibility
        }
        if (StringUtils.isBlank(transformerId) && reference.getProperty(Constants.SERVICE_SHORTNAME) != null) {

            transformerId = reference.getProperty(Constants.SERVICE_SHORTNAME).toString();
        }

        if (StringUtils.isBlank(transformerId)) {
            return;
        }

        String actionProviderId = ACTION_ID_PREFIX + transformerId;

        String attributeName = getAttributeName(reference);

        ActionProvider provider = actionFactory.createActionProvider(actionProviderId, transformerId,
                attributeName);

        Dictionary actionProviderProperties = new Hashtable<String, String>();

        actionProviderProperties.put(Constants.SERVICE_ID, actionProviderId);

        ServiceRegistration actionServiceRegistration = getBundleContext().registerService(PROVIDER_INTERFACE_NAME,
                provider, actionProviderProperties);

        LOGGER.info("Registered new {} [{}]", PROVIDER_INTERFACE_NAME, actionServiceRegistration);

        actionProviderRegistry.put(reference, actionServiceRegistration);

    }

    public void unbind(ServiceReference<MetacardTransformer> reference) {

        LOGGER.info("Service unregistered [" + reference + "]");

        ServiceRegistration actionProviderRegistration = actionProviderRegistry.remove(reference);

        if (actionProviderRegistration != null) {
            actionProviderRegistration.unregister();
            LOGGER.info("Unregistered {} [{}]", PROVIDER_INTERFACE_NAME, actionProviderRegistration);
        }

    }

    /* Determines if this ServiceReference is an AttributeMetacardTransformer.
    If not returns empty string*/
    private String getAttributeName(ServiceReference<MetacardTransformer> serviceReference) {
        if (serviceReference != null) {
            MetacardTransformer transformer = getBundleContext().getService(serviceReference);
            if (transformer instanceof AttributeMetacardTransformer) {
                return ((AttributeMetacardTransformer) transformer).getAttributeName();
            }
        }
        return "";
    }

    protected BundleContext getBundleContext() {
        return FrameworkUtil.getBundle(ActionProviderRegistryProxy.class).getBundleContext();
    }
}