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 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
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 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
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package com.sun.enterprise.v3.server;

import com.sun.enterprise.config.serverbeans.Cluster;
import com.sun.enterprise.config.serverbeans.Clusters;
import com.sun.enterprise.config.serverbeans.Server;
import com.sun.enterprise.config.serverbeans.Domain;
import com.sun.logging.LogDomains;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.glassfish.api.Startup;
import org.glassfish.api.admin.ServerEnvironment;
import org.glassfish.internal.api.GMSService;
import org.jvnet.hk2.annotations.*;
import org.jvnet.hk2.component.*;


/**
 * This service is responsible for loading the group management
 * service. GMS will only be enabled if there is at least one cluster
 * present with the gms-enabled attribute set to true.
 */
// todo: what should this be? default is 5. looking for gms-enabled attribute
// has no effect if not present
//@Priority(3)
@Service(name="GmsLoaderService")
public class GmsLoaderService implements Startup, PreDestroy, PostConstruct {

    final static Logger logger = LogDomains.getLogger(
        GmsLoaderService.class, LogDomains.CORE_LOGGER);

    // todo: check instance name. need to know if das or instance
    @Inject(name=ServerEnvironment.DEFAULT_INSTANCE_NAME)
    Server server;

    @Inject
    ServerEnvironment env;

    @Inject
    Habitat habitat;

    /**
     * Returns the lifecyle of the service. This service may not be needed
     * after startup -- we still need to determine how to load GMS when
     * a gms-enabled cluster is first created during runtime.
     * TODO: determine SERVER v START
     */
    @Override
    public Startup.Lifecycle getLifecycle() {
        return Startup.Lifecycle.SERVER;
    }

    /**
     * Starts the application loader service.
     *
     * Look at the list of existing clusters. Stop after finding the
     * first gms-enabled cluster.
     *
     * todo: in instance, only check *my* cluster (if I'm part of
     * a cluster)
     */
    @Override
    public void postConstruct() {
        Domain domain = habitat.getComponent(Domain.class);
        Clusters clusters = domain.getClusters();
        if (clusters != null) {
            for (Cluster cluster : clusters.getCluster()) {
                String gmsEnString = cluster.getGmsEnabled();
                if (logger.isLoggable(Level.FINE)) {
                    logger.fine(String.format(
                        "cluster %s found with gms-enabled='%s'",
                        cluster.getName(), gmsEnString));
                }
                if(gmsEnString != null && Boolean.parseBoolean(gmsEnString)) {
                    loadService();
                    break;
                }
            }
        }
    }

    private void loadService() {
        // getting the service from the habitat is enough to load it
        GMSService gmss = habitat.getByContract(GMSService.class);
    }

    /**
     * Placeholder -- Stop gms.
     * TODO: need this?
     */
    @Override
    public void preDestroy() {
    }

    @Override
    public String toString() {
        return "GMS Loader";
    }

}