WordsCapitalizer.java

/* MIT License

Copyright (c) 2018 Andrea Ligios

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

package com.andrealigios.legendaryutils;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Locale;

/** 
 * 
 * @author Andrea Ligios
 * @version 1.0.0
 * @see <a href="https://github.com/andrea-ligios/legendary-utils">Legendary Utils</a>
 * 
 * WordsCapitalizer performs a smart words capitalization, respecting Unicode and UTF-16 Surrogate Pairs, and a custom Locale if provided.
 * <p> 
 * Custom delimiters can be specified in order to instruct the engine how to handle each one of those, 
 * by capitalizing only before, only after, or before and after the marker, to handle cases like O'Brian when parsing last names, for example.
 * 
 * Originally posted on November 30, 2012, on StackOverflow: https://stackoverflow.com/a/13649579/1654265
 * 
 */
public class WordsCapitalizer {

    public static String capitalizeEveryWord(String source) {
        return capitalizeEveryWord(source,null,null);
    }

    public static String capitalizeEveryWord(String source, Locale locale) {
        return capitalizeEveryWord(source,null,locale);
    }

    public static String capitalizeEveryWord(String source, List<Delimiter> delimiters, Locale locale) {
        char[] chars; 

        if (delimiters == null || delimiters.size() == 0) {
            delimiters = getDefaultDelimiters();
        }

        // If Locale specified, i18n toLowerCase is executed, to handle specific behaviors (eg. Turkish dotted and dotless 'i')
        if (locale!=null) {
            chars = source.toLowerCase(locale).toCharArray();
        } else { 
            chars = source.toLowerCase().toCharArray();
        }

        // First character ALWAYS capitalized, if it is a Letter.
        if (chars.length>0 && Character.isLetter(chars[0]) && !isSurrogate(chars[0])){
            chars[0] = Character.toUpperCase(chars[0]);
        }

        for (int i = 0; i < chars.length; i++) {
            if (!isSurrogate(chars[i]) && !Character.isLetter(chars[i])) {
                // Current char is not a Letter; gonna check if it is a delimitrer.
                for (Delimiter delimiter : delimiters){
                    if (delimiter.getDelimiter()==chars[i]){
                        // Delimiter found, applying rules...
                        if (delimiter.capitalizeBefore() && i>0 && Character.isLetter(chars[i-1]) && !isSurrogate(chars[i-1])) {   
                        	// previous character is a Letter and I have to capitalize it
                            chars[i-1] = Character.toUpperCase(chars[i-1]);
                        }
                        if (delimiter.capitalizeAfter() && i<chars.length-1 && Character.isLetter(chars[i+1]) && !isSurrogate(chars[i+1])) {   
                        	// next character is a Letter and I have to capitalize it
                            chars[i+1] = Character.toUpperCase(chars[i+1]);
                        }
                        break;
                    }
                } 
            }
        }
        return String.valueOf(chars);
    }

    private static boolean isSurrogate(char chr){
        // Check if the current character is part of an UTF-16 Surrogate Pair.  
        // Note: not validating the pair, just used to bypass (any found part of) it.
        return (Character.isHighSurrogate(chr) || Character.isLowSurrogate(chr));
    }       

    private static List<Delimiter> getDefaultDelimiters(){
        // If no delimiter specified, "Capitalize after space" rule is set by default. 
        List<Delimiter> delimiters = new ArrayList<Delimiter>();
        delimiters.add(new Delimiter(Behavior.CAPITALIZE_AFTER_MARKER, ' '));
        return delimiters;
    } 

    public static class Delimiter {
        private Behavior behavior;
        private char delimiter;

        public Delimiter(Behavior behavior, char delimiter) {
            super();
            this.behavior = behavior;
            this.delimiter = delimiter;
        }

        public boolean capitalizeBefore(){
            return (behavior.equals(Behavior.CAPITALIZE_BEFORE_MARKER) || behavior.equals(Behavior.CAPITALIZE_BEFORE_AND_AFTER_MARKER));
        }

        public boolean capitalizeAfter(){
            return (behavior.equals(Behavior.CAPITALIZE_AFTER_MARKER) || behavior.equals(Behavior.CAPITALIZE_BEFORE_AND_AFTER_MARKER));
        }

        public char getDelimiter() {
            return delimiter;
        }
    }

    public static enum Behavior {
        CAPITALIZE_AFTER_MARKER(0),
        CAPITALIZE_BEFORE_MARKER(1),
        CAPITALIZE_BEFORE_AND_AFTER_MARKER(2);                      

        private int value;

        private Behavior(int value) {
            this.value = value;
        }

        public int getValue() {
            return value;
        }           
    } 
}