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/* * Copyright 2001-2004 The Apache Software Foundation. * * Licensed 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 Soundex value. Soundex is an encoding used to relate similar names, but can also be used as a * general purpose scheme to find word with similar phonemes. * * @author Apache Software Foundation * @version $Id: Soundex.java,v 1.26 2004/07/07 23:15:24 ggregory Exp $ * * @deprecated Please use {@link java.net.URL#openConnection} instead. * Please visit <a href="http://android-developers.blogspot.com/2011/09/androids-http-clients.html">this webpage</a> * for further details. */ @Deprecated public class Soundex implements StringEncoder { /** * An instance of Soundex using the US_ENGLISH_MAPPING mapping. * * @see #US_ENGLISH_MAPPING */ public static final Soundex US_ENGLISH = new Soundex(); /** * This is a default mapping of the 26 letters used in US English. A value of <code>0</code> for a letter position * means do not encode. * <p> * (This constant is provided as both an implementation convenience and to allow Javadoc to pick * up the value for the constant values page.) * </p> * * @see #US_ENGLISH_MAPPING */ public static final String US_ENGLISH_MAPPING_STRING = "01230120022455012623010202"; /** * This is a default mapping of the 26 letters used in US English. A value of <code>0</code> for a letter position * means do not encode. * * @see Soundex#Soundex(char[]) */ public static final char[] US_ENGLISH_MAPPING = US_ENGLISH_MAPPING_STRING.toCharArray(); // BEGIN android-note // Removed @see reference to SoundexUtils below, since the class isn't // public. // END android-note /** * Encodes the Strings and returns the number of characters in the two encoded Strings that are the same. This * return value ranges from 0 through 4: 0 indicates little or no similarity, and 4 indicates strong similarity or * identical values. * * @param s1 * A String that will be encoded and compared. * @param s2 * A String that will be encoded and compared. * @return The number of characters in the two encoded Strings that are the same from 0 to 4. * * @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> * * @throws EncoderException * if an error occurs encoding one of the strings * @since 1.3 */ public int difference(String s1, String s2) throws EncoderException { return SoundexUtils.difference(this, s1, s2); } /** * The maximum length of a Soundex code - Soundex codes are only four characters by definition. * * @deprecated This feature is not needed since the encoding size must be constant. Will be removed in 2.0. */ private int maxLength = 4; /** * Every letter of the alphabet is "mapped" to a numerical value. This char array holds the values to which each * letter is mapped. This implementation contains a default map for US_ENGLISH */ private char[] soundexMapping; /** * Creates an instance using US_ENGLISH_MAPPING * * @see Soundex#Soundex(char[]) * @see Soundex#US_ENGLISH_MAPPING */ public Soundex() { this(US_ENGLISH_MAPPING); } /** * Creates a soundex instance using the given mapping. This constructor can be used to provide an internationalized * mapping for a non-Western character set. * * Every letter of the alphabet is "mapped" to a numerical value. This char array holds the values to which each * letter is mapped. This implementation contains a default map for US_ENGLISH * * @param mapping * Mapping array to use when finding the corresponding code for a given character */ public Soundex(char[] mapping) { this.setSoundexMapping(mapping); } /** * Encodes an Object using the soundex algorithm. This method is provided in order to satisfy the requirements of * the Encoder interface, and will throw an EncoderException if the supplied object is not of type java.lang.String. * * @param pObject * Object to encode * @return An object (or type java.lang.String) containing the soundex code which corresponds to the String * supplied. * @throws EncoderException * if the parameter supplied is not of type java.lang.String * @throws IllegalArgumentException * if a character is not mapped */ public Object encode(Object pObject) throws EncoderException { if (!(pObject instanceof String)) { throw new EncoderException("Parameter supplied to Soundex encode is not of type java.lang.String"); } return soundex((String) pObject); } /** * Encodes a String using the soundex algorithm. * * @param pString * A String object to encode * @return A Soundex code corresponding to the String supplied * @throws IllegalArgumentException * if a character is not mapped */ public String encode(String pString) { return soundex(pString); } /** * Used internally by the SoundEx algorithm. * * Consonants from the same code group separated by W or H are treated as one. * * @param str * the cleaned working string to encode (in upper case). * @param index * the character position to encode * @return Mapping code for a particular character * @throws IllegalArgumentException * if the character is not mapped */ private char getMappingCode(String str, int index) { char mappedChar = this.map(str.charAt(index)); // HW rule check if (index > 1 && mappedChar != '0') { char hwChar = str.charAt(index - 1); if ('H' == hwChar || 'W' == hwChar) { char preHWChar = str.charAt(index - 2); char firstCode = this.map(preHWChar); if (firstCode == mappedChar || 'H' == preHWChar || 'W' == preHWChar) { return 0; } } } return mappedChar; } /** * Returns the maxLength. Standard Soundex * * @deprecated This feature is not needed since the encoding size must be constant. Will be removed in 2.0. * @return int */ public int getMaxLength() { return this.maxLength; } /** * Returns the soundex mapping. * * @return soundexMapping. */ private char[] getSoundexMapping() { return this.soundexMapping; } /** * Maps the given upper-case character to it's Soudex code. * * @param ch * An upper-case character. * @return A Soundex code. * @throws IllegalArgumentException * Thrown if <code>ch</code> is not mapped. */ private char map(char ch) { int index = ch - 'A'; if (index < 0 || index >= this.getSoundexMapping().length) { throw new IllegalArgumentException("The character is not mapped: " + ch); } return this.getSoundexMapping()[index]; } /** * Sets the maxLength. * * @deprecated This feature is not needed since the encoding size must be constant. Will be removed in 2.0. * @param maxLength * The maxLength to set */ public void setMaxLength(int maxLength) { this.maxLength = maxLength; } /** * Sets the soundexMapping. * * @param soundexMapping * The soundexMapping to set. */ private void setSoundexMapping(char[] soundexMapping) { this.soundexMapping = soundexMapping; } /** * Retreives the Soundex code for a given String object. * * @param str * String to encode using the Soundex algorithm * @return A soundex code for the String supplied * @throws IllegalArgumentException * if a character is not mapped */ public String soundex(String str) { if (str == null) { return null; } str = SoundexUtils.clean(str); if (str.length() == 0) { return str; } char out[] = { '0', '0', '0', '0' }; char last, mapped; int incount = 1, count = 1; out[0] = str.charAt(0); last = getMappingCode(str, 0); while ((incount < str.length()) && (count < out.length)) { mapped = getMappingCode(str, incount++); if (mapped != 0) { if ((mapped != '0') && (mapped != last)) { out[count++] = mapped; } last = mapped; } } return new String(out); } }