public void TestSoundexUtilsNullBehaviour()
{
Assert.AreEqual(null, SoundexUtils.Clean(null));
Assert.AreEqual("", SoundexUtils.Clean(""));
Assert.AreEqual(0, SoundexUtils.DifferenceEncoded(null, ""));
Assert.AreEqual(0, SoundexUtils.DifferenceEncoded("", null));
}
/// <summary>
/// Retrieves the Soundex code for a given string.
/// </summary>
/// <param name="str">String to encode using the Soundex algorithm.</param>
/// <returns>A soundex code for the string supplied.</returns>
/// <exception cref="ArgumentException">If a character is not mapped.</exception>
public virtual string GetSoundex(string str)
{
if (str == null)
{
return(null);
}
str = SoundexUtils.Clean(str);
if (str.Length == 0)
{
return(str);
}
char[] output = { '0', '0', '0', '0' };
int count = 0;
char first = str[0];
output[count++] = first;
char lastDigit = Map(first); // previous digit
for (int i = 1; i < str.Length && count < output.Length; i++)
{
char ch = str[i];
if ((this.specialCaseHW) && (ch == 'H' || ch == 'W'))
{ // these are ignored completely
continue;
}
char digit = Map(ch);
if (digit == SILENT_MARKER)
{
continue;
}
if (digit != '0' && digit != lastDigit)
{ // don't store vowels or repeats
output[count++] = digit;
}
lastDigit = digit;
}
return(new string(output));
}
/// <summary>
/// Retrieves the Refined Soundex code for a given string.
/// </summary>
/// <param name="str">String to encode using the Refined Soundex algorithm.</param>
/// <returns>A soundex code for the string supplied.</returns>
public virtual string GetSoundex(string str)
{
if (str == null)
{
return(null);
}
str = SoundexUtils.Clean(str);
if (str.Length == 0)
{
return(str);
}
StringBuilder sBuf = new StringBuilder();
sBuf.Append(str[0]);
char last, current;
last = '*';
for (int i = 0; i < str.Length; i++)
{
current = GetMappingCode(str[i]);
if (current == last)
{
continue;
}
else if (current != 0)
{
sBuf.Append(current);
}
last = current;
}
return(sBuf.ToString());
}
/// <summary>
/// Retrieves the NYSIIS code for a given string.
/// </summary>
/// <param name="str">String to encode using the NYSIIS algorithm.</param>
/// <returns>A NYSIIS code for the string supplied.</returns>
public virtual string GetNysiis(string str)
{
if (str == null)
{
return(null);
}
// Use the same clean rules as Soundex
str = SoundexUtils.Clean(str);
if (str.Length == 0)
{
return(str);
}
// Translate first characters of name:
// MAC -> MCC, KN -> NN, K -> C, PH | PF -> FF, SCH -> SSS
str = PAT_MAC.Replace(str, "MCC", 1);
str = PAT_KN.Replace(str, "NN", 1);
str = PAT_K.Replace(str, "C", 1);
str = PAT_PH_PF.Replace(str, "FF", 1);
str = PAT_SCH.Replace(str, "SSS", 1);
// Translate last characters of name:
// EE -> Y, IE -> Y, DT | RT | RD | NT | ND -> D
str = PAT_EE_IE.Replace(str, "Y", 1);
str = PAT_DT_ETC.Replace(str, "D", 1);
// First character of key = first character of name.
StringBuilder key = new StringBuilder(str.Length);
key.Append(str[0]);
// Transcode remaining characters, incrementing by one character each time
char[] chars = str.ToCharArray();
int len = chars.Length;
for (int i = 1; i < len; i++)
{
char next = i < len - 1 ? chars[i + 1] : SPACE;
char aNext = i < len - 2 ? chars[i + 2] : SPACE;
char[] transcoded = TranscodeRemaining(chars[i - 1], chars[i], next, aNext);
System.Array.Copy(transcoded, 0, chars, i, transcoded.Length);
// only append the current char to the key if it is different from the last one
if (chars[i] != chars[i - 1])
{
key.Append(chars[i]);
}
}
if (key.Length > 1)
{
char lastChar = key[key.Length - 1];
// If last character is S, remove it.
if (lastChar == 'S')
{
//key.deleteCharAt(key.length() - 1);
key.Remove(key.Length - 1, 1);
lastChar = key[key.Length - 1];
}
if (key.Length > 2)
{
char last2Char = key[key.Length - 2];
// If last characters are AY, replace with Y.
if (last2Char == 'A' && lastChar == 'Y')
{
//.key.deleteCharAt(key.length() - 2);
key.Remove(key.Length - 2, 1);
}
}
// If last character is A, remove it.
if (lastChar == 'A')
{
//key.deleteCharAt(key.length() - 1);
key.Remove(key.Length - 1, 1);
}
}
string result = key.ToString();
return(this.IsStrict ? result.Substring(0, Math.Min(TRUE_LENGTH, result.Length) - 0) : result);
}
/// <summary>
/// Returns the number of characters in the two encoded strings that are the
/// same. This return value ranges from 0 to the length of the shortest
/// encoded string: 0 indicates little or no similarity, and 4 out of 4 (for
/// example) indicates strong similarity or identical values. For refined
/// Soundex, the return value can be greater than 4.
/// <para/>
/// See: <a href="http://msdn.microsoft.com/library/default.asp?url=/library/en-us/tsqlref/ts_de-dz_8co5.asp">
/// MS T-SQL DIFFERENCE</a>
/// <para/>
/// since 1.3
/// </summary>
/// <param name="s1">A string that will be encoded and compared.</param>
/// <param name="s2">A string that will be encoded and compared.</param>
/// <returns>The number of characters in the two encoded strings that are the same from 0 to to the length of the shortest encoded string.</returns>
/// <seealso cref="SoundexUtils.Difference(IStringEncoder, string, string)"/>
public virtual int Difference(string s1, string s2)
{
return(SoundexUtils.Difference(this, s1, s2));
}