static int oversize()

in mr/src/main/java/org/elasticsearch/hadoop/util/ArrayUtils.java [101:169]
41 lines of code
14 McCabe index (conditional complexity)

    static int oversize(int minTargetSize, int bytesPerElement) {

        if (minTargetSize < 0) {
            // catch usage that accidentally overflows int
            throw new EsHadoopIllegalArgumentException("invalid array size " + minTargetSize);
        }

        if (minTargetSize == 0) {
            // wait until at least one element is requested
            return 0;
        }

        // asymptotic exponential growth by 1/8th, favors
        // spending a bit more CPU to not tie up too much wasted
        // RAM:
        int extra = minTargetSize >> 3;

        if (extra < 3) {
            // for very small arrays, where constant overhead of
            // realloc is presumably relatively high, we grow
            // faster
            extra = 3;
        }

        int newSize = minTargetSize + extra;

        // add 7 to allow for worst case byte alignment addition below:
        if (newSize + 7 < 0) {
            // int overflowed -- return max allowed array size
            return Integer.MAX_VALUE;
        }

        if (Constants.JRE_IS_64BIT) {
            // round up to 8 byte alignment in 64bit env
            switch (bytesPerElement) {
            case 4:
                // round up to multiple of 2
                return (newSize + 1) & 0x7ffffffe;
            case 2:
                // round up to multiple of 4
                return (newSize + 3) & 0x7ffffffc;
            case 1:
                // round up to multiple of 8
                return (newSize + 7) & 0x7ffffff8;
            case 8:
                // no rounding
            default:
                // odd (invalid?) size
                return newSize;
            }
        }
        else {
            // round up to 4 byte alignment in 64bit env
            switch (bytesPerElement) {
            case 2:
                // round up to multiple of 2
                return (newSize + 1) & 0x7ffffffe;
            case 1:
                // round up to multiple of 4
                return (newSize + 3) & 0x7ffffffc;
            case 4:
            case 8:
                // no rounding
            default:
                // odd (invalid?) size
                return newSize;
            }
        }
    }