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A very lightweight WebSocket client library for Java/Android which aims to implement the WebSocket protocol as defined in RFC 6455

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/*
 * 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 tech.gusavila92.apache.commons.codec.language;

import tech.gusavila92.apache.commons.codec.EncoderException;
import tech.gusavila92.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.
 *
 * This class is thread-safe.
 * Although not strictly immutable, the {@link #maxLength} field is not actually used.
 *
 * @version $Id: Soundex.java 1429868 2013-01-07 16:08:05Z ggregory $
 */
public class Soundex implements StringEncoder {

    /**
     * This is a default mapping of the 26 letters used in US English. A value of 0 for a letter position
     * means do not encode.
     * 

* (This constant is provided as both an implementation convenience and to allow Javadoc to pick * up the value for the constant values page.) *

* * @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 0 for a letter position * means do not encode. * * @see Soundex#Soundex(char[]) */ private static final char[] US_ENGLISH_MAPPING = US_ENGLISH_MAPPING_STRING.toCharArray(); /** * An instance of Soundex using the US_ENGLISH_MAPPING mapping. * * @see #US_ENGLISH_MAPPING */ public static final Soundex US_ENGLISH = new Soundex(); /** * 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. */ @Deprecated 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 final char[] soundexMapping; /** * Creates an instance using US_ENGLISH_MAPPING * * @see Soundex#Soundex(char[]) * @see Soundex#US_ENGLISH_MAPPING */ public Soundex() { this.soundexMapping = 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(final char[] mapping) { this.soundexMapping = new char[mapping.length]; System.arraycopy(mapping, 0, this.soundexMapping, 0, mapping.length); } /** * Creates a refined soundex instance using a custom mapping. This constructor can be used to customize the mapping, * and/or possibly provide an internationalized mapping for a non-Western character set. * * @param mapping * Mapping string to use when finding the corresponding code for a given character * @since 1.4 */ public Soundex(final String mapping) { this.soundexMapping = mapping.toCharArray(); } /** * 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 SoundexUtils#difference(StringEncoder,String,String) * @see MS * T-SQL DIFFERENCE * * @throws EncoderException * if an error occurs encoding one of the strings * @since 1.3 */ public int difference(final String s1, final String s2) throws EncoderException { return SoundexUtils.difference(this, s1, s2); } /** * 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 obj * 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 */ @Override public Object encode(final Object obj) throws EncoderException { if (!(obj instanceof String)) { throw new EncoderException("Parameter supplied to Soundex encode is not of type java.lang.String"); } return soundex((String) obj); } /** * Encodes a String using the soundex algorithm. * * @param str * A String object to encode * @return A Soundex code corresponding to the String supplied * @throws IllegalArgumentException * if a character is not mapped */ @Override public String encode(final String str) { return soundex(str); } /** * 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(final String str, final int index) { // map() throws IllegalArgumentException final char mappedChar = this.map(str.charAt(index)); // HW rule check if (index > 1 && mappedChar != '0') { final char hwChar = str.charAt(index - 1); if ('H' == hwChar || 'W' == hwChar) { final char preHWChar = str.charAt(index - 2); final 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 */ @Deprecated 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 its Soundex code. * * @param ch * An upper-case character. * @return A Soundex code. * @throws IllegalArgumentException * Thrown if ch is not mapped. */ private char map(final char ch) { final 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 */ @Deprecated public void setMaxLength(final int maxLength) { this.maxLength = maxLength; } /** * Retrieves 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; } final char out[] = {'0', '0', '0', '0'}; char last, mapped; int incount = 1, count = 1; out[0] = str.charAt(0); // getMappingCode() throws IllegalArgumentException 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); } }




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