Globals.java

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 * and Distribution License("CDDL") (collectively, the "License").  You
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 * obtain a copy of the License at
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package org.glassfish.internal.api;

import com.sun.enterprise.module.ModulesRegistry;
import com.sun.enterprise.module.single.StaticModulesRegistry;
import org.jvnet.hk2.annotations.Service;
import org.glassfish.common.util.Constants;
import org.glassfish.hk2.api.Rank;
import org.glassfish.hk2.api.ServiceLocator;
import org.glassfish.hk2.runlevel.RunLevel;
import com.sun.enterprise.config.serverbeans.ConfigBeansUtilities;
import javax.inject.Inject;
import javax.inject.Singleton;

/**
 * Very sensitive class, anything stored here cannot be garbage collected
 *
 * @author Jerome Dochez
 */
@Service(name = "globals")
@Singleton
public class Globals {

    private static volatile ServiceLocator defaultHabitat;

    private static Object staticLock = new Object();
    
    // dochez : remove this once we can get rid of ConfigBeanUtilities class
    @SuppressWarnings("unused")
    @Inject
    private ConfigBeansUtilities utilities;
    
    @Inject
    private Globals(ServiceLocator habitat) {
        defaultHabitat = habitat;
    }

    public static ServiceLocator getDefaultBaseServiceLocator() {
    	return getDefaultHabitat();
    }
    
    public static ServiceLocator getDefaultHabitat() {
        return defaultHabitat;
    }

    public static <T> T get(Class<T> type) {
        return defaultHabitat.getService(type);
    }

    public static void setDefaultHabitat(final ServiceLocator habitat) {
        defaultHabitat = habitat;
    }

    public static ServiceLocator getStaticBaseServiceLocator() {
    	return getStaticHabitat();
    }
    
    public static ServiceLocator getStaticHabitat() {
        if (defaultHabitat == null) {
            synchronized (staticLock) {
                if (defaultHabitat == null) {
                    ModulesRegistry modulesRegistry = new StaticModulesRegistry(Globals.class.getClassLoader());
                    defaultHabitat = modulesRegistry.createServiceLocator("default");
                }
            }
        }

        return defaultHabitat;
    }
    
    /**
     * The point of this service is to ensure that the Globals
     * service is properly initialized by the RunLevelService
     * at the InitRunLevel.  However, Globals itself must be
     * of scope Singleton because it us used in contexts where
     * the RunLevelService is not there
     * 
     * @author jwells
     *
     */
    @Service
    @RunLevel(value=(InitRunLevel.VAL - 1), mode=RunLevel.RUNLEVEL_MODE_NON_VALIDATING)
    public static class GlobalsInitializer {
        @SuppressWarnings("unused")
        @Inject
        private Globals globals;
    }
}