private static int readElements()

in mavibot/src/main/java/org/apache/directory/mavibot/btree/BulkLoader.java [102:179]
56 lines of code
10 McCabe index (conditional complexity)

    private static <K, V> int readElements( BTree<K, V> btree, Iterator<Tuple<K, V>> iterator, List<File> sortedFiles,
        List<Tuple<K, V>> tuples, int chunkSize ) throws IOException
    {
        int nbRead = 0;
        int nbIteration = 0;
        int nbElems = 0;
        boolean inMemory = true;
        Set<K> keys = new HashSet<K>();

        while ( true )
        {
            nbIteration++;
            tuples.clear();
            keys.clear();

            // Read up to chukSize elements
            while ( iterator.hasNext() && ( nbRead < chunkSize ) )
            {
                Tuple<K, V> tuple = iterator.next();
                tuples.add( tuple );

                if ( !keys.contains( tuple.getKey() ) )
                {
                    keys.add( tuple.getKey() );
                    nbRead++;
                }
            }

            if ( nbRead < chunkSize )
            {
                if ( nbIteration != 1 )
                {
                    // Flush the sorted data on disk and exit
                    inMemory = false;

                    sortedFiles.add( flushToDisk( nbIteration, tuples, btree ) );
                }

                // Update the number of read elements
                nbElems += nbRead;

                break;
            }
            else
            {
                if ( !iterator.hasNext() )
                {
                    // special case : we have exactly chunkSize elements in the incoming data
                    if ( nbIteration > 1 )
                    {
                        // Flush the sorted data on disk and exit
                        inMemory = false;
                        sortedFiles.add( flushToDisk( nbIteration, tuples, btree ) );
                    }

                    // We have read all the data in one round trip, let's get out, no need
                    // to store the data on disk

                    // Update the number of read elements
                    nbElems += nbRead;

                    break;
                }

                // We have read chunkSize elements, we have to sort them on disk
                nbElems += nbRead;
                nbRead = 0;
                sortedFiles.add( flushToDisk( nbIteration, tuples, btree ) );
            }
        }

        if ( !inMemory )
        {
            tuples.clear();
        }

        return nbElems;
    }