public static int getYearMonth(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        return cal.get(Calendar.YEAR) * 100 + cal.get(Calendar.MONTH) + 1;
    }
{@code CollQueryFunctions} defines function implementation for use in ColQueryTemplates

@author tiwe
querydsl-collections/src/main/java/com/querydsl/collections/CollQueryFunctions.java