Apache Commons Codec Source Code
Apache Commons Codec library
provides implementations of common encoders and decoders such as Base64, Hex,
Phonetic and URLs.
Apache Commons Codec Source Code files are provided in both binary packge (commons-codec-3.15-bin.zip) and source package (commons-codec-3.15-src.zip). You can download them at Apache Commons Codec Website.
Apache Commons Codec Source Code has no dependencies. You can compile it to generate your own version of Apache Commons Codec JAR file.
The source code of Apache Commons Codec 1.15 is provided below:
✍: FYIcenter
⏎ org/apache/commons/codec/language/Soundex.java
/*
* 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 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.
*
* <p>This class is thread-safe.
* Although not strictly immutable, the mutable fields are not actually used.</p>
*/
public class Soundex implements StringEncoder {
/**
* The marker character used to indicate a silent (ignored) character.
* These are ignored except when they appear as the first character.
* <p>
* Note: the {@link #US_ENGLISH_MAPPING_STRING} does not use this mechanism
* because changing it might break existing code. Mappings that don't contain
* a silent marker code are treated as though H and W are silent.
* <p>
* To override this, use the {@link #Soundex(String, boolean)} constructor.
* @since 1.11
*/
public static final char SILENT_MARKER = '-';
/**
* This is a default mapping of the 26 letters used in US English. A value of {@code 0} for a letter position
* means do not encode, but treat as a separator when it occurs between consonants with the same code.
* <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>
* <b>Note that letters H and W are treated specially.</b>
* They are ignored (after the first letter) and don't act as separators
* between consonants with the same code.
*/
// ABCDEFGHIJKLMNOPQRSTUVWXYZ
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} 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.
* This treats H and W as silent letters.
* Apart from when they appear as the first letter, they are ignored.
* They don't act as separators between duplicate codes.
*
* @see #US_ENGLISH_MAPPING_STRING
*/
public static final Soundex US_ENGLISH = new Soundex();
/**
* An instance of Soundex using the Simplified Soundex mapping, as described here:
* http://west-penwith.org.uk/misc/soundex.htm
* <p>
* This treats H and W the same as vowels (AEIOUY).
* Such letters aren't encoded (after the first), but they do
* act as separators when dropping duplicate codes.
* The mapping is otherwise the same as for {@link #US_ENGLISH}
* <p>
* @since 1.11
*/
public static final Soundex US_ENGLISH_SIMPLIFIED = new Soundex(US_ENGLISH_MAPPING_STRING, false);
/**
* An instance of Soundex using the mapping as per the Genealogy site:
* http://www.genealogy.com/articles/research/00000060.html
* <p>
* This treats vowels (AEIOUY), H and W as silent letters.
* Such letters are ignored (after the first) and do not
* act as separators when dropping duplicate codes.
* <p>
* The codes for consonants are otherwise the same as for
* {@link #US_ENGLISH_MAPPING_STRING} and {@link #US_ENGLISH_SIMPLIFIED}
*
* @since 1.11
*/
public static final Soundex US_ENGLISH_GENEALOGY = new Soundex("-123-12--22455-12623-1-2-2");
// ABCDEFGHIJKLMNOPQRSTUVWXYZ
/**
* 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;
/**
* Should H and W be treated specially?
* <p>
* In versions of the code prior to 1.11,
* the code always treated H and W as silent (ignored) letters.
* If this field is false, H and W are no longer special-cased.
*/
private final boolean specialCaseHW;
/**
* Creates an instance using US_ENGLISH_MAPPING
*
* @see Soundex#Soundex(char[])
* @see Soundex#US_ENGLISH_MAPPING_STRING
*/
public Soundex() {
this.soundexMapping = US_ENGLISH_MAPPING;
this.specialCaseHW = true;
}
/**
* 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
* <p>
* If the mapping contains an instance of {@link #SILENT_MARKER} then H and W are not given special treatment
*
* @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);
this.specialCaseHW = !hasMarker(this.soundexMapping);
}
private boolean hasMarker(final char[] mapping) {
for(final char ch : mapping) {
if (ch == SILENT_MARKER) {
return true;
}
}
return false;
}
/**
* 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.
* <p>
* If the mapping contains an instance of {@link #SILENT_MARKER} then H and W are not given special treatment
*
* @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();
this.specialCaseHW = !hasMarker(this.soundexMapping);
}
/**
* 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
* @param specialCaseHW if true, then
* @since 1.11
*/
public Soundex(final String mapping, final boolean specialCaseHW) {
this.soundexMapping = mapping.toCharArray();
this.specialCaseHW = specialCaseHW;
}
/**
* 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 <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(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);
}
/**
* 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;
}
/**
* Maps the given upper-case character to its Soundex code.
*
* @param ch
* An upper-case character.
* @return A Soundex code.
* @throws IllegalArgumentException
* Thrown if {@code ch} is not mapped.
*/
private char map(final char ch) {
final int index = ch - 'A';
if (index < 0 || index >= this.soundexMapping.length) {
throw new IllegalArgumentException("The character is not mapped: " + ch + " (index=" + index + ")");
}
return this.soundexMapping[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'};
int count = 0;
final char first = str.charAt(0);
out[count++] = first;
char lastDigit = map(first); // previous digit
for(int i = 1; i < str.length() && count < out.length ; i++) {
final char ch = str.charAt(i);
if ((this.specialCaseHW) && (ch == 'H' || ch == 'W')) { // these are ignored completely
continue;
}
final char digit = map(ch);
if (digit == SILENT_MARKER) {
continue;
}
if (digit != '0' && digit != lastDigit) { // don't store vowels or repeats
out[count++] = digit;
}
lastDigit = digit;
}
return new String(out);
}
}
⏎ org/apache/commons/codec/language/Soundex.java
Or download all of them as a single archive file:
File name: commons-codec-1.15-sources.jar File size: 364441 bytes Release date: 2020-09-01 Download
⇒ Download and Install commons-codec-1.15-bin.zip
2020-06-28, 106187👍, 1💬
