Query q = sess.createQuery(...);
q.setFirstResult(x);
q.setMaxResults(y);

public class LazyInitList implements List {
    public static final int ALL = Integer.MAX_VALUE;
    private final static Log log = LogFactory.getLog(LazyInitList.class);
    private static final int UNKWOWN = -1;
    private static final int NO_SUPPORTED = 0;
    private static final int SUPPORTED = 1;
    private int resultSetScrollable = UNKWOWN;
    private int pageSize = 20;
    private Query query = null;
    private Criteria criteria = null;
    private List resultList = null;
    private int loadedSize=0;
    private int totalSize=-1;

    public LazyInitList(final Query query) {
        super();
        this.query = query;
    }

    public LazyInitList(final Criteria criteria) {
        super();
        this.criteria = criteria;
    }   
   
    public LazyInitList(final Query query, final int defaultFetchCount) {
        super();
        this.query = query;
        this.pageSize = defaultFetchCount;
    }

    public LazyInitList(final Criteria criteria, final int defaultFetchCount) {
        super();
        this.criteria = criteria;
        this.pageSize = defaultFetchCount;
    } 
   
   
    private List initList(final int pos) {
        if (resultList==null || (pos>loadedSize)) {
            if (query!=null) {
                if (loadedSize<ALL) {
                    loadedSize = loadedSize<pageSize ? pageSize : Math.max(loadedSize*2,pos+pageSize);
                }
                if (pos==ALL) {
                    loadedSize = ALL;
                }
                query.setMaxResults(loadedSize);
                resultList = query.list();
            }
            if (criteria!=null) {
                if (loadedSize<ALL) {
                    loadedSize = loadedSize<pageSize ? pageSize : Math.max(loadedSize*2,pos+pageSize);
                }
                if (pos==ALL) {
                    loadedSize = ALL;
                }
                criteria.setMaxResults(loadedSize);
                resultList = criteria.list();
            }
        }
        return resultList;
    }
   
    /**
     * Return total collection size by using scrollable resultsets
     * with fallback to HQL or Criteria query
     */
    private int getTotalSize() {
        if (totalSize==-1) {
            if (loadedSize==ALL) {
                // If the list is already loaded don't make a separat query
                totalSize=  resultList.size();
            } else {
                if (resultSetScrollable!=NO_SUPPORTED) {
                    // As far as I know there is no way checking for scrollable resultsset
                    // so this is an try and error approach chechkign for scrollable resultsets
                   try {
                      ScrollableResults scrollable = criteria==null ? query.scroll(ScrollMode.SCROLL_SENSITIVE) : criteria.scroll(ScrollMode.SCROLL_SENSITIVE);
                    scrollable.afterLast();
                    scrollable.previous();
                    totalSize = scrollable.getRowNumber()+1;
                    resultSetScrollable = SUPPORTED;
                   } catch (Exception e) {
                       log.warn("ScrollableResults seems not be supported from the database.");
                       resultSetScrollable = NO_SUPPORTED;
                       getTotalSizeByQuery();
                   }
                } else {
                    // return size with separate query
                    getTotalSizeByQuery();
                }
            }
        }
        return totalSize;
    }
   
    /**
     * Return total collection size with a separate
     * HQL or Crieteria query
     */
    private void getTotalSizeByQuery() {
        if (criteria!=null) {
            criteria.setProjection(Projections.rowCount());
            totalSize = ((Integer)(criteria.uniqueResult())).intValue();
            criteria.setProjection(null);
            criteria.setResultTransformer(Criteria.ROOT_ENTITY);
        }
        if (query!=null) {
            initList(ALL);
            totalSize = resultList.size();
        }
    }

    public int getLoadedSize() {
        return loadedSize;
    }
   
    public void add(int index, Object element) {
        initList(index);
        resultList.add(index, element);
    }
    public boolean add(Object o) {
        initList(size());
        return resultList.add(o);
    }
   [...}
}