BeiderMorseEncoder.java
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* 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
*
* https://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,
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*/
package org.apache.commons.codec.language.bm;
import org.apache.commons.codec.EncoderException;
import org.apache.commons.codec.StringEncoder;
/**
* Encodes strings into their Beider-Morse phonetic encoding.
* <p>
* Beider-Morse phonetic encodings are optimized for family names. However, they may be useful for a wide range of words.
* </p>
* <p>
* This encoder is intentionally mutable to allow dynamic configuration through bean properties. As such, it is mutable, and may not be thread-safe. If you
* require a guaranteed thread-safe encoding then use {@link PhoneticEngine} directly.
* </p>
* <h2>Encoding overview</h2>
* <p>
* Beider-Morse phonetic encodings is a multi-step process. Firstly, a table of rules is consulted to guess what language the word comes from. For example, if
* it ends in "{@code ault}" then it infers that the word is French. Next, the word is translated into a phonetic representation using a language-specific
* phonetics table. Some runs of letters can be pronounced in multiple ways, and a single run of letters may be potentially broken up into phonemes at different
* places, so this stage results in a set of possible language-specific phonetic representations. Lastly, this language-specific phonetic representation is
* processed by a table of rules that re-writes it phonetically taking into account systematic pronunciation differences between languages, to move it towards a
* pan-indo-european phonetic representation. Again, sometimes there are multiple ways this could be done and sometimes things that can be pronounced in several
* ways in the source language have only one way to represent them in this average phonetic language, so the result is again a set of phonetic spellings.
* </p>
* <p>
* Some names are treated as having multiple parts. This can be due to two things. Firstly, they may be hyphenated. In this case, each individual hyphenated
* word is encoded, and then these are combined end-to-end for the final encoding. Secondly, some names have standard prefixes, for example, "{@code Mac/Mc}" in
* Scottish (English) names. As sometimes it is ambiguous whether the prefix is intended or is an accident of the spelling, the word is encoded once with the
* prefix and once without it. The resulting encoding contains one and then the other result.
* </p>
* <h2>Encoding format</h2>
* <p>
* Individual phonetic spellings of an input word are represented in upper- and lower-case roman characters. Where there are multiple possible phonetic
* representations, these are joined with a pipe ({@code |}) character. If multiple hyphenated words where found, or if the word may contain a name prefix, each
* encoded word is placed in ellipses and these blocks are then joined with hyphens. For example, "{@code d'ortley}" has a possible prefix. The form without
* prefix encodes to "{@code ortlaj|ortlej}", while the form with prefix encodes to " {@code dortlaj|dortlej}". Thus, the full, combined encoding is
* "{@code (ortlaj|ortlej)-(dortlaj|dortlej)}".
* </p>
* <p>
* The encoded forms are often quite a bit longer than the input strings. This is because a single input may have many potential phonetic interpretations. For
* example, "{@code Renault}" encodes to " {@code rYnDlt|rYnalt|rYnult|rinDlt|rinalt|rinult}". The {@code APPROX} rules will tend to produce larger encodings as
* they consider a wider range of possible, approximate phonetic interpretations of the original word. Down-stream applications may wish to further process the
* encoding for indexing or lookup purposes, for example, by splitting on pipe ({@code |}) and indexing under each of these alternatives.
* </p>
* <p>
* <strong>Note</strong>: this version of the Beider-Morse encoding is equivalent with v3.4 of the reference implementation.
* </p>
* <p>
* This class is Not ThreadSafe.
* </p>
*
* @see <a href="https://stevemorse.org/phonetics/bmpm.htm">Beider-Morse Phonetic Matching</a>
* @see <a href="https://stevemorse.org/phoneticinfo.htm">Reference implementation</a>
* @since 1.6
*/
public class BeiderMorseEncoder implements StringEncoder {
/**
* Creates a new builder for a Beider-Morse encoder.
*
* @since 1.23.0
*/
public static final class Builder {
private PhoneticEngine engine = PhoneticEngine.builder().get();
private Builder() {
// empty.
}
/**
* Gets a new Beider-Morse encoder with the current configuration.
*
* @return a new Beider-Morse encoder with the current configuration.
*/
public BeiderMorseEncoder get() {
return new BeiderMorseEncoder(this);
}
/**
* Sets the phonetic engine to use.
*
* @param engine the phonetic engine to use.
* @return this builder, for chaining.
*/
public Builder setPhoneticEngine(final PhoneticEngine engine) {
this.engine = engine != null ? engine : PhoneticEngine.builder().get();
return this;
}
}
/**
* Creates a new builder for a BeiderMorseEncoder.
*
* @return a new builder for a BeiderMorseEncoder.
* @since 1.23.0
*/
public static Builder builder() {
return new Builder();
}
/** A cached object. */
private PhoneticEngine engine = PhoneticEngine.builder().get();
/**
* Constructs a new instance.
*
* @deprecated Use {@link #builder()} to create a new instance.
*/
public BeiderMorseEncoder() {
// empty
}
private BeiderMorseEncoder(final Builder builder) {
engine = builder.engine;
}
@Override
public Object encode(final Object source) throws EncoderException {
if (!(source instanceof String)) {
throw new EncoderException("BeiderMorseEncoder encode parameter is not of type String");
}
return encode((String) source);
}
@Override
public String encode(final String source) throws EncoderException {
return source != null ? engine.encode(source) : null;
}
/**
* Gets the name type currently in operation.
*
* @return The NameType currently being used.
*/
public NameType getNameType() {
return engine.getNameType();
}
/**
* Gets the rule type currently in operation.
*
* @return The RuleType currently being used.
*/
public RuleType getRuleType() {
return engine.getRuleType();
}
/**
* Tests if multiple possible encodings are concatenated.
*
* @return true if multiple encodings are concatenated, false if just the first one is returned.
*/
public boolean isConcat() {
return engine.isConcat();
}
/**
* Sets how multiple possible phonetic encodings are combined.
*
* @param concat true if multiple encodings are to be combined with a '|', false if just the first one is to be considered.
*/
public void setConcat(final boolean concat) {
engine = PhoneticEngine.builder().setAll(engine).setConcat(concat).get();
}
/**
* Sets the number of maximum of phonemes that shall be considered by the engine.
* <p>
* A value less than 0 will reset the maximum number of phonemes to the default {@value PhoneticEngine.Builder#MAX_PHONEMES}.
* </p>
*
* @param maxPhonemes the maximum number of phonemes returned by the engine.
* @since 1.7
*/
public void setMaxPhonemes(final int maxPhonemes) {
engine = PhoneticEngine.builder().setAll(engine).setMaxPhonemes(maxPhonemes).get();
}
/**
* Sets the type of name. Use {@link NameType#GENERIC} unless you specifically want phonetic encodings optimized for Ashkenazi or Sephardic Jewish family
* names.
* <p>
* A null value will reset the name type to the default of {@link NameType#GENERIC}.
* </p>
*
* @param nameType the NameType in use.
*/
public void setNameType(final NameType nameType) {
engine = PhoneticEngine.builder().setAll(engine).setNameType(nameType).get();
}
/**
* Sets the rule type to apply. This will widen or narrow the range of phonetic encodings considered.
* <p>
* A null value will reset the rule type to the default of {@link RuleType#APPROX}.
* </p>
*
* @param ruleType {@link RuleType#APPROX} or {@link RuleType#EXACT} for approximate or exact phonetic matches.
*/
public void setRuleType(final RuleType ruleType) {
engine = PhoneticEngine.builder().setAll(engine).setRuleType(ruleType).get();
}
}