public boolean isEmpty()

in bytekit-core/src/main/java/com/alibaba/bytekit/utils/concurrent/ConcurrentWeakKeyHashMap.java [756:786]

• 20 lines of code
• 7 McCabe index (conditional complexity)

    public boolean isEmpty() {
        final Segment<K, V>[] segments = this.segments;
        /*
         * We keep track of per-segment modCounts to avoid ABA problems in which
         * an element in one segment was added and in another removed during
         * traversal, in which case the table was never actually empty at any
         * point. Note the similar use of modCounts in the size() and
         * containsValue() methods, which are the only other methods also
         * susceptible to ABA problems.
         */
        int[] mc = new int[segments.length];
        int mcsum = 0;
        for (int i = 0; i < segments.length; ++ i) {
            if (segments[i].count != 0) {
                return false;
            } else {
                mcsum += mc[i] = segments[i].modCount;
            }
        }
        // If mcsum happens to be zero, then we know we got a snapshot before
        // any modifications at all were made.  This is probably common enough
        // to bother tracking.
        if (mcsum != 0) {
            for (int i = 0; i < segments.length; ++ i) {
                if (segments[i].count != 0 || mc[i] != segments[i].modCount) {
                    return false;
                }
            }
        }
        return true;
    }