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There is a newer version: 2024.0.2
package shz.core.st.triest;

import shz.core.function.BytePredicate;
import shz.core.function.ToByteFunction;
import shz.core.queue.a.BArrayQueue;
import shz.core.queue.a.LArrayQueue;
import shz.core.stack.l.LLinkedStack;

/**
 * 值为byte类型的基于单词查找树的符号表
 * 
 * 8+24+2*r(r为chars数组长度)=chars
 * 8+(48+8*r)*n(n为元素个数)+8*r*n*w(w为键的平均长度)
 * 

 * B=8+48*(n+1)+8*r*n*(w+1)+(2*r+对齐填充)
 */
public class ConcurrentBTrieST extends ConcurrentTrieST {
    private static final long serialVersionUID = 4309927609415464143L;

    /**
     * 1+25+8*r(r为数组长度)+对齐填充=32+8*r
     * 
     * B=48+8*r
     */
    protected static final class Node extends ConcurrentTrieST.Node {
        private static final long serialVersionUID = -2275470732245528315L;
        public byte val;

        public Node(int r) {
            super(new Node[r]);
        }
    }

    public ConcurrentBTrieST(char[] chars) {
        super(chars);
        root = new Node(chars.length);
    }

    public static ConcurrentBTrieST of(char[] chars) {
        return new ConcurrentBTrieST(chars);
    }

    public final void put(char[] a, byte val) {
        acceptWrite(() -> {
            Node x = root;
            for (char c : a) {
                int i = charIndex.idx(c);
                if (x.next[i] == null) x.next[i] = new Node(len);
                x = x.next[i];
            }
            x.val = val;
            x.leaf = true;
        });
    }

    public final Byte get(char[] a, int d) {
        return applyRead(() -> {
            Node x = get(root, a, d);
            return x == null || !x.leaf ? null : x.val;
        });
    }

    public final Byte get(char[] a) {
        return get(a, a.length);
    }

    public final BArrayQueue getAll() {
        return applyRead(() -> get(root));
    }

    protected final BArrayQueue get(Node x) {
        BArrayQueue queue = BArrayQueue.of();
        if (x != null) {
            LLinkedStack stack = LLinkedStack.of();
            push(stack, x);
            while (!stack.isEmpty()) {
                Node pop = stack.pop();
                if (pop.leaf) queue.offer(pop.val);
                push(stack, pop);
            }
        }
        return queue;
    }

    private void push(LLinkedStack stack, Node x) {
        if (x.next == null) return;
        for (int i = 0; i < len; ++i) if (x.next[i] != null) stack.push(x.next[i]);
    }

    public final BArrayQueue getByPrefix(char[] prefix) {
        return applyRead(() -> get(get(root, prefix, prefix.length)));
    }

    public final LArrayQueue getChars(BytePredicate predicate, int limit) {
        return applyRead(() -> getChars0(x -> predicate == null || predicate.test(x.val), limit));
    }

    public final byte computeIfAbsent(char[] a, ToByteFunction func) {
        Byte oldVal = get(a);
        if (oldVal != null) return oldVal;
        return applyWrite(() -> {
            Node x = get(root, a, a.length);
            if (x != null && x.leaf) return x.val;
            byte val = func.applyAsByte(a);
            put(a, val);
            return val;
        });
    }
}