supportclass.cs

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        {
            if (s == null) 
            {
                throw new ArgumentException("null");
            }

            if (radix < MIN_RADIX) 
            {
                throw new NotSupportedException("radix " + radix +
                    " less than Number.MIN_RADIX");
            }
            if (radix > MAX_RADIX) 
            {
                throw new NotSupportedException("radix " + radix +
                    " greater than Number.MAX_RADIX");
            }

            long result = 0;
            long mult = 1;

            s = s.ToLower();
			
            for (int i = s.Length - 1; i >= 0; i--)
            {
                int weight = digits.IndexOf(s[i]);
                if (weight == -1)
                    throw new FormatException("Invalid number for the specified radix");

                result += (weight * mult);
                mult *= radix;
            }

            return result;
        }

        /// <summary>
        /// Performs an unsigned bitwise right shift with the specified number
        /// </summary>
        /// <param name="number">Number to operate on</param>
        /// <param name="bits">Ammount of bits to shift</param>
        /// <returns>The resulting number from the shift operation</returns>
        public static int URShift(int number, int bits)
        {
            if (number >= 0)
                return number >> bits;
            else
                return (number >> bits) + (2 << ~bits);
        }


        /// <summary>
        /// Performs an unsigned bitwise right shift with the specified number
        /// </summary>
        /// <param name="number">Number to operate on</param>
        /// <param name="bits">Ammount of bits to shift</param>
        /// <returns>The resulting number from the shift operation</returns>
        public static long URShift(long number, int bits)
        {
            if (number >= 0)
                return number >> bits;
            else
                return (number >> bits) + (2 << ~bits);
        }


        /// <summary>
        /// Returns the index of the first bit that is set to true that occurs 
        /// on or after the specified starting index. If no such bit exists 
        /// then -1 is returned.
        /// </summary>
        /// <param name="bits">The BitArray object.</param>
        /// <param name="fromIndex">The index to start checking from (inclusive).</param>
        /// <returns>The index of the next set bit.</returns>
        public static int NextSetBit(System.Collections.BitArray bits, int fromIndex)
        {
            for (int i = fromIndex; i < bits.Length; i++)
            {
                if (bits[i] == true)
                {
                    return i;
                }
            }
            return -1;
        }
    }

    /// <summary>
    /// Mimics Java's Character class.
    /// </summary>
    public class Character
    {
        private const char charNull= '\0';
        private const char charZero = '0';
        private const char charA = 'a';

        /// <summary>
        /// </summary>
        public static int MAX_RADIX
        {
            get
            {
                return 36;
            }
        }

        /// <summary>
        /// </summary>
        public static int MIN_RADIX
        {
            get
            {
                return 2;
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="digit"></param>
        /// <param name="radix"></param>
        /// <returns></returns>
        public static char ForDigit(int digit, int radix)
        {
            // if radix or digit is out of range,
            // return the null character.
            if (radix < Character.MIN_RADIX)
                return charNull;
            if (radix > Character.MAX_RADIX)
                return charNull;
            if (digit < 0)
                return charNull;
            if (digit >= radix)
                return charNull;

            // if digit is less than 10,
            // return '0' plus digit
            if (digit < 10)
                return (char) ( (int) charZero + digit);

            // otherwise, return 'a' plus digit.
            return (char) ((int) charA + digit - 10);
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public class Date
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="dateTime"></param>
        /// <returns></returns>
        static public long GetTime(DateTime dateTime)
        {
            TimeSpan ts = dateTime.Subtract(new DateTime(1970, 1, 1));
            ts = ts.Subtract(TimeZone.CurrentTimeZone.GetUtcOffset(dateTime));
            return ts.Ticks / TimeSpan.TicksPerMillisecond;
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public class Single
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="s"></param>
        /// <param name="style"></param>
        /// <param name="provider"></param>
        /// <returns></returns>
        public static System.Single Parse(System.String s, System.Globalization.NumberStyles style, System.IFormatProvider provider)
        {
            try
            {
                if (s.EndsWith("f") || s.EndsWith("F"))
                    return System.Single.Parse(s.Substring(0, s.Length - 1), style, provider);
                else
                    return System.Single.Parse(s, style, provider);
            }
            catch (System.FormatException fex)
            {
                throw fex;					
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="s"></param>
        /// <param name="provider"></param>
        /// <returns></returns>
        public static System.Single Parse(System.String s, System.IFormatProvider provider)
        {
            try
            {
                if (s.EndsWith("f") || s.EndsWith("F"))
                    return System.Single.Parse(s.Substring(0, s.Length - 1), provider);
                else
                    return System.Single.Parse(s, provider);
            }
            catch (System.FormatException fex)
            {
                throw fex;					
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="s"></param>
        /// <param name="style"></param>
        /// <returns></returns>
        public static System.Single Parse(System.String s, System.Globalization.NumberStyles style)
        {
            try
            {
                if (s.EndsWith("f") || s.EndsWith("F"))
                    return System.Single.Parse(s.Substring(0, s.Length - 1), style);
                else
                    return System.Single.Parse(s, style);
            }
            catch(System.FormatException fex)
            {
                throw fex;					
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="s"></param>
        /// <returns></returns>
        public static System.Single Parse(System.String s)
        {
            try
            {
                if (s.EndsWith("f") || s.EndsWith("F"))
                    return System.Single.Parse(s.Substring(0, s.Length - 1));
                else
                    return System.Single.Parse(s);
            }
            catch(System.FormatException fex)
            {
                throw fex;					
            }
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public class AppSettings
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="key"></param>
        /// <param name="defValue"></param>
        /// <returns></returns>
        public static int Get(System.String key, int defValue)
        {
            System.String theValue = System.Configuration.ConfigurationSettings.AppSettings.Get(key);
            if (theValue == null)
            {
                return defValue;
            }
            return System.Convert.ToInt16(theValue.Trim());
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="key"></param>
        /// <param name="defValue"></param>
        /// <returns></returns>
        public static long Get(System.String key, long defValue)
        {
            System.String theValue = System.Configuration.ConfigurationSettings.AppSettings.Get(key);
            if (theValue == null)
            {
                return defValue;
            }
            return System.Convert.ToInt32(theValue.Trim());
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="key"></param>
        /// <param name="defValue"></param>
        /// <returns></returns>
        public static System.String Get(System.String key, System.String defValue)
        {
            System.String theValue = System.Configuration.ConfigurationSettings.AppSettings.Get(key);
            if (theValue == null)
            {
                return defValue;
            }
            return theValue;
        }
    }

    public static System.Collections.SortedList TailMap(System.Collections.SortedList list, System.Object limit)
    {
        System.Collections.Comparer comparer = System.Collections.Comparer.Default;
        System.Collections.SortedList newList = new System.Collections.SortedList();

        if (list != null)
        {
            if (list.Count > 0)
            {
                int index = 0;
                while (comparer.Compare(list.GetKey(index), limit) < 0)
                    index++;

                for (; index < list.Count; index++)
                    newList.Add(list.GetKey(index), list[list.GetKey(index)]);
            }
        }

        return newList;
    }

    /// <summary>
    /// Use for .NET 1.1 Framework only.
    /// </summary>
    public class CompressionSupport
    {
        public interface ICompressionAdapter
        {
            byte[] Compress(byte[] input);
            byte[] Uncompress(byte[] input);
        }

        private static ICompressionAdapter compressionAdapter;

        public static byte[] Uncompress(byte[] input)
        {
            CheckCompressionSupport();
            return compressionAdapter.Uncompress(input);
        }

        public static byte[] Compress(byte[] input)
        {
            CheckCompressionSupport();
            return compressionAdapter.Compress(input);
        }

        private static void CheckCompressionSupport()
        {
            if (compressionAdapter == null)
            {
                System.String compressionLibClassName = SupportClass.AppSettings.Get("Lucene.Net.CompressionLib.class", null);
                if (compressionLibClassName == null)
                    throw new System.SystemException("Compression support not configured"); 

                Type compressionLibClass = Type.GetType(compressionLibClassName, true);
                System.Object compressionAdapterObj = Activator.CreateInstance(compressionLibClass);
                compressionAdapter = compressionAdapterObj as ICompressionAdapter;
                if (compressionAdapter == null)
                    throw new System.SystemException("Compression adapter does not support the ICompressionAdapter interface");
            }
        }
    }
}