/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.codec.language;
import org.apache.commons.codec.EncoderException;
import org.apache.commons.codec.StringEncoder;
/**
* Encodes a string into a double metaphone value. This Implementation is based
* on the algorithm by <CITE>Lawrence Philips</CITE>.
* <p>
* This class is conditionally thread-safe. The instance field
* {@link #maxCodeLen} is mutable {@link #setMaxCodeLen(int)} but is not
* volatile, and accesses are not synchronized. If an instance of the class is
* shared between threads, the caller needs to ensure that suitable
* synchronization is used to ensure safe publication of the value between
* threads, and must not invoke {@link #setMaxCodeLen(int)} after initial setup.
*
* @see <a href="http://drdobbs.com/184401251?pgno=2">Original Article</a>
* @see <a
* href="http://en.wikipedia.org/wiki/Metaphone">http://en.wikipedia.org/wiki/Metaphone</a>
*
* @version $Id: DoubleMetaphone.java 1378724 2012-08-29 21:02:47Z tn $
*/
public class DoubleMetaphone implements StringEncoder {
/**
* "Vowels" to test for
*/
private static final String VOWELS = "AEIOUY";
/**
* Prefixes when present which are not pronounced
*/
private static final String[] SILENT_START = { "GN", "KN", "PN", "WR", "PS" };
private static final String[] L_R_N_M_B_H_F_V_W_SPACE = { "L", "R", "N",
"M", "B", "H", "F", "V", "W", " " };
private static final String[] ES_EP_EB_EL_EY_IB_IL_IN_IE_EI_ER = { "ES",
"EP", "EB", "EL", "EY", "IB", "IL", "IN", "IE", "EI", "ER" };
private static final String[] L_T_K_S_N_M_B_Z = { "L", "T", "K", "S", "N",
"M", "B", "Z" };
/**
* Maximum length of an encoding, default is 4
*/
private int maxCodeLen = 4;
/**
* Creates an instance of this DoubleMetaphone encoder
*/
public DoubleMetaphone() {
super();
}
/**
* Encode a value with Double Metaphone.
*
* @param value
* String to encode
* @return an encoded string
*/
public String doubleMetaphone(String value) {
return doubleMetaphone(value, false);
}
/**
* Encode a value with Double Metaphone, optionally using the alternate
* encoding.
*
* @param value
* String to encode
* @param alternate
* use alternate encode
* @return an encoded string
*/
public String doubleMetaphone(String value, boolean alternate) {
value = cleanInput(value);
if (value == null) {
return null;
}
boolean slavoGermanic = isSlavoGermanic(value);
int index = isSilentStart(value) ? 1 : 0;
DoubleMetaphoneResult result = new DoubleMetaphoneResult(
this.getMaxCodeLen());
while (!result.isComplete() && index <= value.length() - 1) {
switch (value.charAt(index)) {
case 'A':
case 'E':
case 'I':
case 'O':
case 'U':
case 'Y':
index = handleAEIOUY(result, index);
break;
case 'B':
result.append('P');
index = charAt(value, index + 1) == 'B' ? index + 2 : index + 1;
break;
case '\u00C7':
// A C with a Cedilla
result.append('S');
index++;
break;
case 'C':
index = handleC(value, result, index);
break;
case 'D':
index = handleD(value, result, index);
break;
case 'F':
result.append('F');
index = charAt(value, index + 1) == 'F' ? index + 2 : index + 1;
break;
case 'G':
index = handleG(value, result, index, slavoGermanic);
break;
case 'H':
index = handleH(value, result, index);
break;
case 'J':
index = handleJ(value, result, index, slavoGermanic);
break;
case 'K':
result.append('K');
index = charAt(value, index + 1) == 'K' ? index + 2 : index + 1;
break;
case 'L':
index = handleL(value, result, index);
break;
case 'M':
result.append('M');
index = conditionM0(value, index) ? index + 2 : index + 1;
break;
case 'N':
result.append('N');
index = charAt(value, index + 1) == 'N' ? index + 2 : index + 1;
break;
case '\u00D1':
// N with a tilde (spanish ene)
result.append('N');
index++;
break;
case 'P':
index = handleP(value, result, index);
break;
case 'Q':
result.append('K');
index = charAt(value, index + 1) == 'Q' ? index + 2 : index + 1;
break;
case 'R':
index = handleR(value, result, index, slavoGermanic);
break;
case 'S':
index = handleS(value, result, index, slavoGermanic);
break;
case 'T':
index = handleT(value, result, index);
break;
case 'V':
result.append('F');
index = charAt(value, index + 1) == 'V' ? index + 2 : index + 1;
break;
case 'W':
index = handleW(value, result, index);
break;
case 'X':
index = handleX(value, result, index);
break;
case 'Z':
index = handleZ(value, result, index, slavoGermanic);
break;
default:
index++;
break;
}
}
return alternate ? result.getAlternate() : result.getPrimary();
}
/**
* Encode the value using DoubleMetaphone. It will only work if
* <code>obj</code> is a <code>String</code> (like <code>Metaphone</code>).
*
* @param obj
* Object to encode (should be of type String)
* @return An encoded Object (will be of type String)
* @throws EncoderException
* encode parameter is not of type String
*/
@Override
public Object encode(Object obj) throws EncoderException {
if (!(obj instanceof String)) {
throw new EncoderException(
"DoubleMetaphone encode parameter is not of type String");
}
return doubleMetaphone((String) obj);
}
/**
* Encode the value using DoubleMetaphone.
*
* @param value
* String to encode
* @return An encoded String
*/
@Override
public String encode(String value) {
return doubleMetaphone(value);
}
/**
* Check if the Double Metaphone values of two <code>String</code> values
* are equal.
*
* @param value1
* The left-hand side of the encoded
* {@link String#equals(Object)}.
* @param value2
* The right-hand side of the encoded
* {@link String#equals(Object)}.
* @return {@code true} if the encoded <code>String</code>s are equal;
* {@code false} otherwise.
* @see #isDoubleMetaphoneEqual(String,String,boolean)
*/
public boolean isDoubleMetaphoneEqual(String value1, String value2) {
return isDoubleMetaphoneEqual(value1, value2, false);
}
/**
* Check if the Double Metaphone values of two <code>String</code> values
* are equal, optionally using the alternate value.
*
* @param value1
* The left-hand side of the encoded
* {@link String#equals(Object)}.
* @param value2
* The right-hand side of the encoded
* {@link String#equals(Object)}.
* @param alternate
* use the alternate value if {@code true}.
* @return {@code true} if the encoded <code>String</code>s are equal;
* {@code false} otherwise.
*/
public boolean isDoubleMetaphoneEqual(String value1, String value2,
boolean alternate) {
return doubleMetaphone(value1, alternate).equals(
doubleMetaphone(value2, alternate));
}
/**
* Returns the maxCodeLen.
*
* @return int
*/
public int getMaxCodeLen() {
return this.maxCodeLen;
}
/**
* Sets the maxCodeLen.
*
* @param maxCodeLen
* The maxCodeLen to set
*/
public void setMaxCodeLen(int maxCodeLen) {
this.maxCodeLen = maxCodeLen;
}
// -- BEGIN HANDLERS --//
/**
* Handles 'A', 'E', 'I', 'O', 'U', and 'Y' cases.
*/
private int handleAEIOUY(DoubleMetaphoneResult result, int index) {
if (index == 0) {
result.append('A');
}
return index + 1;
}
/**
* Handles 'C' cases.
*/
private int handleC(String value, DoubleMetaphoneResult result, int index) {
if (conditionC0(value, index)) { // very confusing, moved out
result.append('K');
index += 2;
} else if (index == 0 && contains(value, index, 6, "CAESAR")) {
result.append('S');
index += 2;
} else if (contains(value, index, 2, "CH")) {
index = handleCH(value, result, index);
} else if (contains(value, index, 2, "CZ")
&& !contains(value, index - 2, 4, "WICZ")) {
// -- "Czerny" --//
result.append('S', 'X');
index += 2;
} else if (contains(value, index + 1, 3, "CIA")) {
// -- "focaccia" --//
result.append('X');
index += 3;
} else if (contains(value, index, 2, "CC")
&& !(index == 1 && charAt(value, 0) == 'M')) {
// -- double "cc" but not "McClelland" --//
return handleCC(value, result, index);
} else if (contains(value, index, 2, "CK", "CG", "CQ")) {
result.append('K');
index += 2;
} else if (contains(value, index, 2, "CI", "CE", "CY")) {
// -- Italian vs. English --//
if (contains(value, index, 3, "CIO", "CIE", "CIA")) {
result.append('S', 'X');
} else {
result.append('S');
}
index += 2;
} else {
result.append('K');
if (contains(value, index + 1, 2, " C", " Q", " G")) {
// -- Mac Caffrey, Mac Gregor --//
index += 3;
} else if (contains(value, index + 1, 1, "C", "K", "Q")
&& !contains(value, index + 1, 2, "CE", "CI")) {
index += 2;
} else {
index++;
}
}
return index;
}
/**
* Handles 'CC' cases.
*/
private int handleCC(String value, DoubleMetaphoneResult result, int index) {
if (contains(value, index + 2, 1, "I", "E", "H")
&& !contains(value, index + 2, 2, "HU")) {
// -- "bellocchio" but not "bacchus" --//
if ((index == 1 && charAt(value, index - 1) == 'A')
|| contains(value, index - 1, 5, "UCCEE", "UCCES")) {
// -- "accident", "accede", "succeed" --//
result.append("KS");
} else {
// -- "bacci", "bertucci", other Italian --//
result.append('X');
}
index += 3;
} else { // Pierce's rule
result.append('K');
index += 2;
}
return index;
}
/**
* Handles 'CH' cases.
*/
private int handleCH(String value, DoubleMetaphoneResult result, int index) {
if (index > 0 && contains(value, index, 4, "CHAE")) { // Michael
result.append('K', 'X');
return index + 2;
} else if (conditionCH0(value, index)) {
// -- Greek roots ("chemistry", "chorus", etc.) --//
result.append('K');
return index + 2;
} else if (conditionCH1(value, index)) {
// -- Germanic, Greek, or otherwise 'ch' for 'kh' sound --//
result.append('K');
return index + 2;
} else {
if (index > 0) {
if (contains(value, 0, 2, "MC")) {
result.append('K');
} else {
result.append('X', 'K');
}
} else {
result.append('X');
}
return index + 2;
}
}
/**
* Handles 'D' cases.
*/
private int handleD(String value, DoubleMetaphoneResult result, int index) {
if (contains(value, index, 2, "DG")) {
// -- "Edge" --//
if (contains(value, index + 2, 1, "I", "E", "Y")) {
result.append('J');
index += 3;
// -- "Edgar" --//
} else {
result.append("TK");
index += 2;
}
} else if (contains(value, index, 2, "DT", "DD")) {
result.append('T');
index += 2;
} else {
result.append('T');
index++;
}
return index;
}
/**
* Handles 'G' cases.
*/
private int handleG(String value, DoubleMetaphoneResult result, int index,
boolean slavoGermanic) {
if (charAt(value, index + 1) == 'H') {
index = handleGH(value, result, index);
} else if (charAt(value, index + 1) == 'N') {
if (index == 1 && isVowel(charAt(value, 0)) && !slavoGermanic) {
result.append("KN", "N");
} else if (!contains(value, index + 2, 2, "EY")
&& charAt(value, index + 1) != 'Y' && !slavoGermanic) {
result.append("N", "KN");
} else {
result.append("KN");
}
index = index + 2;
} else if (contains(value, index + 1, 2, "LI") && !slavoGermanic) {
result.append("KL", "L");
index += 2;
} else if (index == 0
&& (charAt(value, index + 1) == 'Y' || contains(value,
index + 1, 2, ES_EP_EB_EL_EY_IB_IL_IN_IE_EI_ER))) {
// -- -ges-, -gep-, -gel-, -gie- at beginning --//
result.append('K', 'J');
index += 2;
} else if ((contains(value, index + 1, 2, "ER") || charAt(value,
index + 1) == 'Y')
&& !contains(value, 0, 6, "DANGER", "RANGER", "MANGER")
&& !contains(value, index - 1, 1, "E", "I")
&& !contains(value, index - 1, 3, "RGY", "OGY")) {
// -- -ger-, -gy- --//
result.append('K', 'J');
index += 2;
} else if (contains(value, index + 1, 1, "E", "I", "Y")
|| contains(value, index - 1, 4, "AGGI", "OGGI")) {
// -- Italian "biaggi" --//
if (contains(value, 0, 4, "VAN ", "VON ")
|| contains(value, 0, 3, "SCH")
|| contains(value, index + 1, 2, "ET")) {
// -- obvious germanic --//
result.append('K');
} else if (contains(value, index + 1, 3, "IER")) {
result.append('J');
} else {
result.append('J', 'K');
}
index += 2;
} else if (charAt(value, index + 1) == 'G') {
index += 2;
result.append('K');
} else {
index++;
result.append('K');
}
return index;
}
/**
* Handles 'GH' cases.
*/
private int handleGH(String value, DoubleMetaphoneResult result, int index) {
if (index > 0 && !isVowel(charAt(value, index - 1))) {
result.append('K');
index += 2;
} else if (index == 0) {
if (charAt(value, index + 2) == 'I') {
result.append('J');
} else {
result.append('K');
}
index += 2;
} else if ((index > 1 && contains(value, index - 2, 1, "B", "H", "D"))
|| (index > 2 && contains(value, index - 3, 1, "B", "H", "D"))
|| (index > 3 && contains(value, index - 4, 1, "B", "H"))) {
// -- Parker's rule (with some further refinements) - "hugh"
index += 2;
} else {
if (index > 2 && charAt(value, index - 1) == 'U'
&& contains(value, index - 3, 1, "C", "G", "L", "R", "T")) {
// -- "laugh", "McLaughlin", "cough", "gough", "rough", "tough"
result.append('F');
} else if (index > 0 && charAt(value, index - 1) != 'I') {
result.append('K');
}
index += 2;
}
return index;
}
/**
* Handles 'H' cases.
*/
private int handleH(String value, DoubleMetaphoneResult result, int index) {
// -- only keep if first & before vowel or between 2 vowels --//
if ((index == 0 || isVowel(charAt(value, index - 1)))
&& isVowel(charAt(value, index + 1))) {
result.append('H');
index += 2;
// -- also takes car of "HH" --//
} else {
index++;
}
return index;
}
/**
* Handles 'J' cases.
*/
private int handleJ(String value, DoubleMetaphoneResult result, int index,
boolean slavoGermanic) {
if (contains(value, index, 4, "JOSE") || contains(value, 0, 4, "SAN ")) {
// -- obvious Spanish, "Jose", "San Jacinto" --//
if ((index == 0 && (charAt(value, index + 4) == ' ') || value
.length() == 4) || contains(value, 0, 4, "SAN ")) {
result.append('H');
} else {
result.append('J', 'H');
}
index++;
} else {
if (index == 0 && !contains(value, index, 4, "JOSE")) {
result.append('J', 'A');
} else if (isVowel(charAt(value, index - 1))
&& !slavoGermanic
&& (charAt(value, index + 1) == 'A' || charAt(value,
index + 1) == 'O')) {
result.append('J', 'H');
} else if (index == value.length() - 1) {
result.append('J', ' ');
} else if (!contains(value, index + 1, 1, L_T_K_S_N_M_B_Z)
&& !contains(value, index - 1, 1, "S", "K", "L")) {
result.append('J');
}
if (charAt(value, index + 1) == 'J') {
index += 2;
} else {
index++;
}
}
return index;
}
/**
* Handles 'L' cases.
*/
private int handleL(String value, DoubleMetaphoneResult result, int index) {
if (charAt(value, index + 1) == 'L') {
if (conditionL0(value, index)) {
result.appendPrimary('L');
} else {
result.append('L');
}
index += 2;
} else {
index++;
result.append('L');
}
return index;
}
/**
* Handles 'P' cases.
*/
private int handleP(String value, DoubleMetaphoneResult result, int index) {
if (charAt(value, index + 1) == 'H') {
result.append('F');
index += 2;
} else {
result.append('P');
index = contains(value, index + 1, 1, "P", "B") ? index + 2
: index + 1;
}
return index;
}
/**
* Handles 'R' cases.
*/
private int handleR(String value, DoubleMetaphoneResult result, int index,
boolean slavoGermanic) {
if (index == value.length() - 1 && !slavoGermanic
&& contains(value, index - 2, 2, "IE")
&& !contains(value, index - 4, 2, "ME", "MA")) {
result.appendAlternate('R');
} else {
result.append('R');
}
return charAt(value, index + 1) == 'R' ? index + 2 : index + 1;
}
/**
* Handles 'S' cases.
*/
private int handleS(String value, DoubleMetaphoneResult result, int index,
boolean slavoGermanic) {
if (contains(value, index - 1, 3, "ISL", "YSL")) {
// -- special cases "island", "isle", "carlisle", "carlysle" --//
index++;
} else if (index == 0 && contains(value, index, 5, "SUGAR")) {
// -- special case "sugar-" --//
result.append('X', 'S');
index++;
} else if (contains(value, index, 2, "SH")) {
if (contains(value, index + 1, 4, "HEIM", "HOEK", "HOLM", "HOLZ")) {
// -- germanic --//
result.append('S');
} else {
result.append('X');
}
index += 2;
} else if (contains(value, index, 3, "SIO", "SIA")
|| contains(value, index, 4, "SIAN")) {
// -- Italian and Armenian --//
if (slavoGermanic) {
result.append('S');
} else {
result.append('S', 'X');
}
index += 3;
} else if ((index == 0 && contains(value, index + 1, 1, "M", "N", "L",
"W")) || contains(value, index + 1, 1, "Z")) {
// -- german & anglicisations, e.g. "smith" match "schmidt" //
// "snider" match "schneider" --//
// -- also, -sz- in slavic language altho in hungarian it //
// is pronounced "s" --//
result.append('S', 'X');
index = contains(value, index + 1, 1, "Z") ? index + 2 : index + 1;
} else if (contains(value, index, 2, "SC")) {
index = handleSC(value, result, index);
} else {
if (index == value.length() - 1
&& contains(value, index - 2, 2, "AI", "OI")) {
// -- french e.g. "resnais", "artois" --//
result.appendAlternate('S');
} else {
result.append('S');
}
index = contains(value, index + 1, 1, "S", "Z") ? index + 2
: index + 1;
}
return index;
}
/**
* Handles 'SC' cases.
*/
private int handleSC(String value, DoubleMetaphoneResult result, int index) {
if (charAt(value, index + 2) == 'H') {
// -- Schlesinger's rule --//
if (contains(value, index + 3, 2, "OO", "ER", "EN", "UY", "ED",
"EM")) {
// -- Dutch origin, e.g. "school", "schooner" --//
if (contains(value, index + 3, 2, "ER", "EN")) {
// -- "schermerhorn", "schenker" --//
result.append("X", "SK");
} else {
result.append("SK");
}
} else {
if (index == 0 && !isVowel(charAt(value, 3))
&& charAt(value, 3) != 'W') {
result.append('X', 'S');
} else {
result.append('X');
}
}
} else if (contains(value, index + 2, 1, "I", "E", "Y")) {
result.append('S');
} else {
result.append("SK");
}
return index + 3;
}
/**
* Handles 'T' cases.
*/
private int handleT(String value, DoubleMetaphoneResult result, int index) {
if (contains(value, index, 4, "TION")) {
result.append('X');
index += 3;
} else if (contains(value, index, 3, "TIA", "TCH")) {
result.append('X');
index += 3;
} else if (contains(value, index, 2, "TH")
|| contains(value, index, 3, "TTH")) {
if (contains(value, index + 2, 2, "OM", "AM")
||
// -- special case "thomas", "thames" or germanic --//
contains(value, 0, 4, "VAN ", "VON ")
|| contains(value, 0, 3, "SCH")) {
result.append('T');
} else {
result.append('0', 'T');
}
index += 2;
} else {
result.append('T');
index = contains(value, index + 1, 1, "T", "D") ? index + 2
: index + 1;
}
return index;
}
/**
* Handles 'W' cases.
*/
private int handleW(String value, DoubleMetaphoneResult result, int index) {
if (contains(value, index, 2, "WR")) {
// -- can also be in middle of word --//
result.append('R');
index += 2;
} else {
if (index == 0
&& (isVowel(charAt(value, index + 1)) || contains(value,
index, 2, "WH"))) {
if (isVowel(charAt(value, index + 1))) {
// -- Wasserman should match Vasserman --//
result.append('A', 'F');
} else {
// -- need Uomo to match Womo --//
result.append('A');
}
index++;
} else if ((index == value.length() - 1 && isVowel(charAt(value,
index - 1)))
|| contains(value, index - 1, 5, "EWSKI", "EWSKY", "OWSKI",
"OWSKY") || contains(value, 0, 3, "SCH")) {
// -- Arnow should match Arnoff --//
result.appendAlternate('F');
index++;
} else if (contains(value, index, 4, "WICZ", "WITZ")) {
// -- Polish e.g. "filipowicz" --//
result.append("TS", "FX");
index += 4;
} else {
index++;
}
}
return index;
}
/**
* Handles 'X' cases.
*/
private int handleX(String value, DoubleMetaphoneResult result, int index) {
if (index == 0) {
result.append('S');
index++;
} else {
if (!((index == value.length() - 1) && (contains(value, index - 3,
3, "IAU", "EAU") || contains(value, index - 2, 2, "AU",
"OU")))) {
// -- French e.g. breaux --//
result.append("KS");
}
index = contains(value, index + 1, 1, "C", "X") ? index + 2
: index + 1;
}
return index;
}
/**
* Handles 'Z' cases.
*/
private int handleZ(String value, DoubleMetaphoneResult result, int index,
boolean slavoGermanic) {
if (charAt(value, index + 1) == 'H') {
// -- Chinese pinyin e.g. "zhao" or Angelina "Zhang" --//
result.append('J');
index += 2;
} else {
if (contains(value, index + 1, 2, "ZO", "ZI", "ZA")
|| (slavoGermanic && (index > 0 && charAt(value, index - 1) != 'T'))) {
result.append("S", "TS");
} else {
result.append('S');
}
index = charAt(value, index + 1) == 'Z' ? index + 2 : index + 1;
}
return index;
}
// -- BEGIN CONDITIONS --//
/**
* Complex condition 0 for 'C'.
*/
private boolean conditionC0(String value, int index) {
if (contains(value, index, 4, "CHIA")) {
return true;
} else if (index <= 1) {
return false;
} else if (isVowel(charAt(value, index - 2))) {
return false;
} else if (!contains(value, index - 1, 3, "ACH")) {
return false;
} else {
char c = charAt(value, index + 2);
return (c != 'I' && c != 'E')
|| contains(value, index - 2, 6, "BACHER", "MACHER");
}
}
/**
* Complex condition 0 for 'CH'.
*/
private boolean conditionCH0(String value, int index) {
if (index != 0) {
return false;
} else if (!contains(value, index + 1, 5, "HARAC", "HARIS")
&& !contains(value, index + 1, 3, "HOR", "HYM", "HIA", "HEM")) {
return false;
} else if (contains(value, 0, 5, "CHORE")) {
return false;
} else {
return true;
}
}
/**
* Complex condition 1 for 'CH'.
*/
private boolean conditionCH1(String value, int index) {
return ((contains(value, 0, 4, "VAN ", "VON ") || contains(value, 0, 3,
"SCH"))
|| contains(value, index - 2, 6, "ORCHES", "ARCHIT", "ORCHID")
|| contains(value, index + 2, 1, "T", "S") || ((contains(value,
index - 1, 1, "A", "O", "U", "E") || index == 0) && (contains(
value, index + 2, 1, L_R_N_M_B_H_F_V_W_SPACE) || index + 1 == value
.length() - 1)));
}
/**
* Complex condition 0 for 'L'.
*/
private boolean conditionL0(String value, int index) {
if (index == value.length() - 3
&& contains(value, index - 1, 4, "ILLO", "ILLA", "ALLE")) {
return true;
} else if ((contains(value, value.length() - 2, 2, "AS", "OS") || contains(
value, value.length() - 1, 1, "A", "O"))
&& contains(value, index - 1, 4, "ALLE")) {
return true;
} else {
return false;
}
}
/**
* Complex condition 0 for 'M'.
*/
private boolean conditionM0(String value, int index) {
if (charAt(value, index + 1) == 'M') {
return true;
}
return contains(value, index - 1, 3, "UMB")
&& ((index + 1) == value.length() - 1 || contains(value,
index + 2, 2, "ER"));
}
// -- BEGIN HELPER FUNCTIONS --//
/**
* Determines whether or not a value is of slavo-germanic orgin. A value is
* of slavo-germanic origin if it contians any of 'W', 'K', 'CZ', or 'WITZ'.
*/
private boolean isSlavoGermanic(String value) {
return value.indexOf('W') > -1 || value.indexOf('K') > -1
|| value.indexOf("CZ") > -1 || value.indexOf("WITZ") > -1;
}
/**
* Determines whether or not a character is a vowel or not
*/
private boolean isVowel(char ch) {
return VOWELS.indexOf(ch) != -1;
}
/**
* Determines whether or not the value starts with a silent letter. It will
* return {@code true} if the value starts with any of 'GN', 'KN', 'PN',
* 'WR' or 'PS'.
*/
private boolean isSilentStart(String value) {
boolean result = false;
for (String element : SILENT_START) {
if (value.startsWith(element)) {
result = true;
break;
}
}
return result;
}
/**
* Cleans the input.
*/
private String cleanInput(String input) {
if (input == null) {
return null;
}
input = input.trim();
if (input.length() == 0) {
return null;
}
return input.toUpperCase(java.util.Locale.ENGLISH);
}
/**
* Gets the character at index <code>index</code> if available, otherwise it
* returns <code>Character.MIN_VALUE</code> so that there is some sort of a
* default.
*/
protected char charAt(String value, int index) {
if (index < 0 || index >= value.length()) {
return Character.MIN_VALUE;
}
return value.charAt(index);
}
/**
* Shortcut method with 1 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria) {
return contains(value, start, length, new String[] { criteria });
}
/**
* Shortcut method with 2 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria1, String criteria2) {
return contains(value, start, length, new String[] { criteria1,
criteria2 });
}
/**
* Shortcut method with 3 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria1, String criteria2, String criteria3) {
return contains(value, start, length, new String[] { criteria1,
criteria2, criteria3 });
}
/**
* Shortcut method with 4 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria1, String criteria2, String criteria3,
String criteria4) {
return contains(value, start, length, new String[] { criteria1,
criteria2, criteria3, criteria4 });
}
/**
* Shortcut method with 5 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria1, String criteria2, String criteria3,
String criteria4, String criteria5) {
return contains(value, start, length, new String[] { criteria1,
criteria2, criteria3, criteria4, criteria5 });
}
/**
* Shortcut method with 6 criteria.
*/
private static boolean contains(String value, int start, int length,
String criteria1, String criteria2, String criteria3,
String criteria4, String criteria5, String criteria6) {
return contains(value, start, length, new String[] { criteria1,
criteria2, criteria3, criteria4, criteria5, criteria6 });
}
/**
* Determines whether <code>value</code> contains any of the criteria
* starting at index <code>start</code> and matching up to length
* <code>length</code>.
*/
protected static boolean contains(String value, int start, int length,
String[] criteria) {
boolean result = false;
if (start >= 0 && start + length <= value.length()) {
String target = value.substring(start, start + length);
for (String element : criteria) {
if (target.equals(element)) {
result = true;
break;
}
}
}
return result;
}
// -- BEGIN INNER CLASSES --//
/**
* Inner class for storing results, since there is the optional alternate
* encoding.
*/
public class DoubleMetaphoneResult {
private final StringBuilder primary = new StringBuilder(getMaxCodeLen());
private final StringBuilder alternate = new StringBuilder(
getMaxCodeLen());
private final int maxLength;
public DoubleMetaphoneResult(int maxLength) {
this.maxLength = maxLength;
}
public void append(char value) {
appendPrimary(value);
appendAlternate(value);
}
public void append(char primary, char alternate) {
appendPrimary(primary);
appendAlternate(alternate);
}
public void appendPrimary(char value) {
if (this.primary.length() < this.maxLength) {
this.primary.append(value);
}
}
public void appendAlternate(char value) {
if (this.alternate.length() < this.maxLength) {
this.alternate.append(value);
}
}
public void append(String value) {
appendPrimary(value);
appendAlternate(value);
}
public void append(String primary, String alternate) {
appendPrimary(primary);
appendAlternate(alternate);
}
public void appendPrimary(String value) {
int addChars = this.maxLength - this.primary.length();
if (value.length() <= addChars) {
this.primary.append(value);
} else {
this.primary.append(value.substring(0, addChars));
}
}
public void appendAlternate(String value) {
int addChars = this.maxLength - this.alternate.length();
if (value.length() <= addChars) {
this.alternate.append(value);
} else {
this.alternate.append(value.substring(0, addChars));
}
}
public String getPrimary() {
return this.primary.toString();
}
public String getAlternate() {
return this.alternate.toString();
}
public boolean isComplete() {
return this.primary.length() >= this.maxLength
&& this.alternate.length() >= this.maxLength;
}
}
}