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jersey-all is a rebundled verison of Jersey as one OSGi bundle.
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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2012 Oracle and/or its affiliates. All rights reserved.
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package org.glassfish.hk2.api;

/**
 * This cache can be used in some circumstances when there can be only one
 * of a service.  This is useful and can avoid an expensive lookup in certain
 * context implementations
 * 
 * @author jwells
 * @param  The type of service stored and returned from this cache
 *
 */
public interface SingleCache {
    /**
     * This can be used for scopes that will only every be created once.
     * The returned value must have been set previously with setCache.
     * If this is called when isCacheSet is false will result in a
     * RuntimeException
     * 
     * @return A value cached with this ActiveDescriptor
     */
    public T getCache();
    
    /**
     * Returns true if this cache has been set
     * 
     * @return true if there is a currently cached value, false
     * otherwise
     */
    public boolean isCacheSet();
    
    /**
     * Sets the value into the cache
     * 
     * @param cacheMe A single value that can be cached in this
     * active descriptor
     */
    public void setCache(T cacheMe);
    
    /**
     * Removes the cached value and makes it such
     * that this cache has not been set
     */
    public void releaseCache();

}