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/*
 * Copyright (c) 2002-2016 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */
package org.neo4j.kernel.impl.util;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Supplier;

import org.neo4j.graphdb.DependencyResolver;

@SuppressWarnings( "rawtypes" )
public class Dependencies extends DependencyResolver.Adapter implements DependencySatisfier
{
    private final Supplier parent;
    private final Map, List> typeDependencies = new HashMap<>();

    public Dependencies()
    {
        parent = null;
    }

    public Dependencies( final DependencyResolver parent )
    {
        this.parent = () -> parent;
    }

    public Dependencies( Supplier parent )
    {
        this.parent = parent;
    }

    @Override
    public  T resolveDependency( Class type, SelectionStrategy selector )
    {
        List options = typeDependencies.get( type );

        if (options != null)
        {
            return selector.select( type, (Iterable) options);
        }

        // Try parent
        if (parent != null)
        {
            DependencyResolver dependencyResolver = parent.get();

            if (dependencyResolver !=null)
                return dependencyResolver.resolveDependency( type, selector );
        }

        // Out of options
        throw new UnsatisfiedDependencyException( type );
    }

    public  Supplier provideDependency( final Class type, final SelectionStrategy selector)
    {
        return () -> resolveDependency( type, selector );
    }

    public  Supplier provideDependency( final Class type )
    {
        return () -> resolveDependency( type );
    }

    @Override
    public  T satisfyDependency( T dependency )
    {
        // File this object under all its possible types
        Class type = dependency.getClass();
        do
        {
            List