org.javimmutable.collections.hash.hamt.HamtEmptyNode Maven / Gradle / Ivy

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//
// Burton Computer Corporation
// http://www.burton-computer.com
//
// Copyright (c) 2017, Burton Computer Corporation
// All rights reserved.
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//     Redistributions in binary form must reproduce the above copyright
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package org.javimmutable.collections.hash.hamt;

import org.javimmutable.collections.Cursor;
import org.javimmutable.collections.Holder;
import org.javimmutable.collections.Holders;
import org.javimmutable.collections.JImmutableMap;
import org.javimmutable.collections.SplitableIterator;
import org.javimmutable.collections.common.MutableDelta;
import org.javimmutable.collections.cursors.StandardCursor;
import org.javimmutable.collections.hash.collision_map.CollisionMap;
import org.javimmutable.collections.iterators.EmptyIterator;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

public class HamtEmptyNode
    implements HamtNode
{
    private static final HamtEmptyNode EMPTY = new HamtEmptyNode();


    @SuppressWarnings("unchecked")
    public static  HamtNode of()
    {
        return EMPTY;
    }

    @Override
    public Holder find(@Nonnull CollisionMap collisionMap,
                          int hashCode,
                          @Nonnull K hashKey)
    {
        return Holders.of();
    }

    @Override
    public V getValueOr(@Nonnull CollisionMap collisionMap,
                        int hashCode,
                        @Nonnull K hashKey,
                        V defaultValue)
    {
        return defaultValue;
    }

    @Nonnull
    @Override
    public HamtNode assign(@Nonnull CollisionMap collisionMap,
                                    int hashCode,
                                    @Nonnull K hashKey,
                                    @Nullable V value,
                                    @Nonnull MutableDelta sizeDelta)
    {
        return new HamtLeafNode<>(hashCode, collisionMap.update(null, hashKey, value, sizeDelta));
    }

    @Nonnull
    @Override
    public HamtNode delete(@Nonnull CollisionMap collisionMap,
                                    int hashCode,
                                    @Nonnull K hashKey,
                                    @Nonnull MutableDelta sizeDelta)
    {
        return this;
    }

    @Override
    public boolean isEmpty()
    {
        return true;
    }

    @Nonnull
    @Override
    public SplitableIterator> iterator(CollisionMap collisionMap)
    {
        return EmptyIterator.of();
    }

    @Nonnull
    @Override
    public Cursor> cursor(CollisionMap collisionMap)
    {
        return StandardCursor.of();
    }

    @Nonnull
    @Override
    public SplitableIterator iterator()
    {
        return EmptyIterator.of();
    }

    @Nonnull
    @Override
    public Cursor cursor()
    {
        return StandardCursor.of();
    }
}