IntSet.java

/*
 * Copyright (C) 2011, Google Inc. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.eclipse.jgit.internal.storage.pack;

class IntSet {
    private int[] set;

    private int cnt;

    IntSet() {
        set = new int[64];
    }

    boolean add(int key) {
        int high = cnt;
        int low = 0;

        if (high == 0) {
            set[0] = key;
            cnt = 1;
            return true;
        }

        do {
            int p = (low + high) >>> 1;
            if (key < set[p])
                high = p;
            else if (key == set[p])
                return false;
            else
                low = p + 1;
        } while (low < high);

        if (cnt == set.length) {
            int[] n = new int[set.length * 2];
            System.arraycopy(set, 0, n, 0, cnt);
            set = n;
        }

        if (low < cnt)
            System.arraycopy(set, low, set, low + 1, cnt - low);
        set[low] = key;
        cnt++;
        return true;
    }
}