public BeanEntry create()

in org.eclipse.sisu.inject/src/org/eclipse/sisu/inject/BeanCache.java [59:107]

• 41 lines of code
• 7 McCabe index (conditional complexity)

    public BeanEntry<Q, T> create( final Q qualifier, final Binding<T> binding, final int rank )
    {
        LazyBeanEntry newBean;

        Object o, n;

        /*
         * Compare-and-swap approach; avoids locking without missing any updates
         */
        do
        {
            o = get();
            if ( null == o )
            {
                // most common case: adding the one (and-only) entry
                n = newBean = new LazyBeanEntry( qualifier, binding, rank );
            }
            else if ( o instanceof LazyBeanEntry )
            {
                final LazyBeanEntry oldBean = (LazyBeanEntry) o;
                if ( binding == oldBean.binding )
                {
                    return oldBean;
                }
                n = createMap( oldBean, newBean = new LazyBeanEntry( qualifier, binding, rank ) );
            }
            else
            {
                synchronized ( this )
                {
                    final Map<Binding, LazyBeanEntry> map = (Map) o;
                    if ( null == ( newBean = map.get( binding ) ) )
                    {
                        map.put( binding, newBean = new LazyBeanEntry( qualifier, binding, rank ) );
                        mutated = true;
                    }
                    return newBean;
                }
            }
        }
        while ( !compareAndSet( o, n ) );

        if ( n instanceof IdentityHashMap )
        {
            mutated = true; // entry was upgraded to map, enable readCache
        }

        return newBean;
    }