public ByteBuffer merge()

in src/java/org/apache/cassandra/db/context/CounterContext.java [296:398]
85 lines of code
26 McCabe index (conditional complexity)

    public ByteBuffer merge(ByteBuffer left, ByteBuffer right)
    {
        boolean leftIsSuperSet = true;
        boolean rightIsSuperSet = true;

        int globalCount = 0;
        int localCount = 0;
        int remoteCount = 0;

        ContextState leftState = ContextState.wrap(left);
        ContextState rightState = ContextState.wrap(right);

        while (leftState.hasRemaining() && rightState.hasRemaining())
        {
            int cmp = leftState.compareIdTo(rightState);
            if (cmp == 0)
            {
                Relationship rel = compare(leftState, rightState);
                if (rel == Relationship.GREATER_THAN)
                    rightIsSuperSet = false;
                else if (rel == Relationship.LESS_THAN)
                    leftIsSuperSet = false;
                else if (rel == Relationship.DISJOINT)
                    leftIsSuperSet = rightIsSuperSet = false;

                if (leftState.isGlobal() || rightState.isGlobal())
                    globalCount += 1;
                else if (leftState.isLocal() || rightState.isLocal())
                    localCount += 1;
                else
                    remoteCount += 1;

                leftState.moveToNext();
                rightState.moveToNext();
            }
            else if (cmp > 0)
            {
                leftIsSuperSet = false;

                if (rightState.isGlobal())
                    globalCount += 1;
                else if (rightState.isLocal())
                    localCount += 1;
                else
                    remoteCount += 1;

                rightState.moveToNext();
            }
            else // cmp < 0
            {
                rightIsSuperSet = false;

                if (leftState.isGlobal())
                    globalCount += 1;
                else if (leftState.isLocal())
                    localCount += 1;
                else
                    remoteCount += 1;

                leftState.moveToNext();
            }
        }

        if (leftState.hasRemaining())
            rightIsSuperSet = false;
        else if (rightState.hasRemaining())
            leftIsSuperSet = false;

        // if one of the contexts is a superset, return it early.
        if (leftIsSuperSet)
            return left;
        else if (rightIsSuperSet)
            return right;

        while (leftState.hasRemaining())
        {
            if (leftState.isGlobal())
                globalCount += 1;
            else if (leftState.isLocal())
                localCount += 1;
            else
                remoteCount += 1;

            leftState.moveToNext();
        }

        while (rightState.hasRemaining())
        {
            if (rightState.isGlobal())
                globalCount += 1;
            else if (rightState.isLocal())
                localCount += 1;
            else
                remoteCount += 1;

            rightState.moveToNext();
        }

        leftState.reset();
        rightState.reset();

        return merge(ContextState.allocate(globalCount, localCount, remoteCount), leftState, rightState);
    }