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diff --git a/src/org/apache/commons/codec/language/Soundex.java b/src/org/apache/commons/codec/language/Soundex.java
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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 $
+ */
+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);
+    }
+
+}