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// Copyright (c) 2003-present, Jodd Team (http://jodd.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
package jodd.util;
import java.io.Serializable;
import java.util.Comparator;
/**
* Probably the best natural strings comparator.
*/
public class NaturalOrderComparator implements Comparator, Serializable {
/* copied from Perl6 code */
private static final char[] ACCENT_CHARS = new char[]{
'À', 'A', 'Á', 'A', 'Â', 'A', 'Ã', 'A', 'Ä', 'A', 'Å', 'A',
'à', 'a', 'á', 'a', 'â', 'a', 'ã', 'a', 'ä', 'a', 'å', 'a',
'Ç', 'C', 'ç', 'c',
'È', 'E', 'É', 'E', 'Ê', 'E', 'Ë', 'E',
'è', 'e', 'é', 'e', 'ê', 'e', 'ë', 'e',
'Ì', 'I', 'Í', 'I', 'Î', 'I', 'Ï', 'I',
'ì', 'i', 'í', 'i', 'î', 'i', 'ï', 'i',
'Ò', 'O', 'Ó', 'O', 'Ô', 'O', 'Õ', 'O', 'Ö', 'O',
'Ø', 'O', 'ò', 'o', 'ó', 'o', 'ô', 'o', 'õ', 'o', 'ö', 'o', 'ø', 'o',
'Ñ', 'N', 'ñ', 'n',
'Ù', 'U', 'Ú', 'U', 'Û', 'U', 'Ü', 'U', 'ù', 'u', 'ú', 'u', 'û', 'u', 'ü', 'u',
'Ý', 'Y', 'ÿ', 'y', 'ý', 'y',
};
protected final boolean ignoreCase;
protected final boolean ignoreAccents;
public NaturalOrderComparator() {
this(false, true);
}
public NaturalOrderComparator(final boolean ignoreCase, final boolean ignoreAccents) {
this.ignoreCase = ignoreCase;
this.ignoreAccents = ignoreAccents;
}
/**
* Compare digits at certain position in two strings.
* The longest run of digits wins. That aside, the greatest
* value wins.
*/
protected int compareDigits(final String str1, int ndx1, final String str2, int ndx2) {
int bias = 0;
while (true) {
char char1 = charAt(str1, ndx1);
char char2 = charAt(str2, ndx2);
boolean isDigitChar1 = CharUtil.isDigit(char1);
boolean isDigitChar2 = CharUtil.isDigit(char2);
if (!isDigitChar1 && !isDigitChar2) {
return bias;
}
if (!isDigitChar1) {
return -1;
}
if (!isDigitChar2) {
return 1;
}
if (char1 < char2) {
if (bias == 0) {
bias = -1;
}
} else if (char1 > char2) {
if (bias == 0) {
bias = 1;
}
} else if (char1 == 0 && char2 == 0) {
return bias;
}
ndx1++;
ndx2++;
}
}
@Override
public int compare(final T o1, final T o2) {
String str1 = o1.toString();
String str2 = o2.toString();
if (ignoreAccents) {
str1 = StringUtil.replace(str1, "ß", "ss");
str2 = StringUtil.replace(str2, "ß", "ss");
str1 = StringUtil.replace(str1, "æ", "ae");
str2 = StringUtil.replace(str2, "æ", "ae");
str1 = StringUtil.replace(str1, "Æ", "AE");
str2 = StringUtil.replace(str2, "Æ", "AE");
}
int ndx1 = 0, ndx2 = 0;
int zeroCount1, zeroCount2;
int zerosDelta = 0;
int lastAllZerosResult = 0;
char char1, char2;
int result;
while (true) {
// only count the number of zeroes leading the last number compared
zeroCount1 = zeroCount2 = 0;
char1 = charAt(str1, ndx1);
char2 = charAt(str2, ndx2);
// skip over leading spaces or zeros in both strings
while (Character.isSpaceChar(char1) || char1 == '0') {
if (char1 == '0') {
zeroCount1++;
} else {
zeroCount1 = 0; // counts only last 0 prefixes, space char interrupts the array of 0s
}
ndx1++;
char1 = charAt(str1, ndx1);
}
while (Character.isSpaceChar(char2) || char2 == '0') {
if (char2 == '0') {
zeroCount2++;
} else {
zeroCount2 = 0;
}
ndx2++;
char2 = charAt(str2, ndx2);
}
if (zeroCount1 > 0 || zeroCount2 > 0) {
zerosDelta = zeroCount1 - zeroCount2;
}
// process remaining digits
boolean isDigitChar1 = CharUtil.isDigit(char1);
boolean isDigitChar2 = CharUtil.isDigit(char2);
if (isDigitChar1 && isDigitChar2) {
result = compareDigits(str1, ndx1, str2, ndx2);
if (result != 0) {
// not equals, return
return result;
}
// if numbers are equal
if (zeroCount1 != zeroCount2) {
return zerosDelta;
}
}
if (char1 == 0 && char2 == 0) {
// both strings end; the strings are the same
if (lastAllZerosResult == 0) {
return zerosDelta;
}
return lastAllZerosResult;
}
// check when one of the numbers is just zeros; as the other
// string is still a number
if (isDigitChar1 || isDigitChar2) {
if (zeroCount1 > 0 && zeroCount2 > 0) {
if (zeroCount1 != zeroCount2) {
return -zerosDelta;
}
}
}
// check if both numbers are zeros
if (zerosDelta != 0) {
// so we really have both number with at least one zero?
if (zeroCount1 > 0 && zeroCount2 > 0) {
lastAllZerosResult = zerosDelta;
} else {
// one of the number is empty strings
// the other char defines the order!
if (zeroCount1 > 0) {
if (char2 > '0') {
return -zerosDelta;
} else {
return zerosDelta;
}
} else if (zeroCount2 > 0) {
if (char1 > '0') {
return -zerosDelta;
}
else {
return zerosDelta;
}
}
return 0;
}
}
// compare chars
if (ignoreCase) {
char1 = Character.toLowerCase(char1);
char2 = Character.toLowerCase(char2);
}
if (ignoreAccents) {
char1 = fixAccent(char1);
char2 = fixAccent(char2);
}
if (char1 < char2) {
return -1;
}
if (char1 > char2) {
return 1;
}
ndx1++;
ndx2++;
}
}
/**
* Fixes accent char.
*/
private char fixAccent(final char c) {
for (int i = 0; i < ACCENT_CHARS.length; i+=2) {
char accentChar = ACCENT_CHARS[i];
if (accentChar == c) {
return ACCENT_CHARS[i + 1];
}
}
return c;
}
/**
* Safe {@code charAt} that returns 0 when ndx is out of boundaries.
*/
private static char charAt(final String string, final int ndx) {
if (ndx >= string.length()) {
return 0;
}
return string.charAt(ndx);
}
}