org.javimmutable.collections.list.ListHelper Maven / Gradle / Ivy

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//
// Burton Computer Corporation
// http://www.burton-computer.com
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// Copyright (c) 2017, Burton Computer Corporation
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package org.javimmutable.collections.list;

final class ListHelper
{
    private static final Object[] EMPTY_VALUES = new Object[0];
    private static final Node[] EMPTY_NODES = new Node[0];

    @SuppressWarnings("unchecked")
    static  Node[] allocateNodes(int size)
    {
        return (Node[])((size == 0) ? EMPTY_NODES : new Node[size]);
    }

    @SuppressWarnings("unchecked")
    static  T[] allocateValues(int size)
    {
        return (T[])((size == 0) ? EMPTY_VALUES : new Object[size]);
    }

    static  Node[] allocateSingleNode(Node node)
    {
        Node[] answer = allocateNodes(1);
        answer[0] = node;
        return answer;
    }

    static int sizeForDepth(int depth)
    {
        return 1 << (5 * depth);
    }
}