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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package sun.util.locale;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Locale.*;
import static java.util.Locale.FilteringMode.*;
import static java.util.Locale.LanguageRange.*;
import java.util.Map;
import java.util.Set;

Implementation for BCP47 Locale matching
/** * Implementation for BCP47 Locale matching * */
public final class LocaleMatcher { public static List<Locale> filter(List<LanguageRange> priorityList, Collection<Locale> locales, FilteringMode mode) { if (priorityList.isEmpty() || locales.isEmpty()) { return new ArrayList<>(); // need to return a empty mutable List } // Create a list of language tags to be matched. List<String> tags = new ArrayList<>(); for (Locale locale : locales) { tags.add(locale.toLanguageTag()); } // Filter language tags. List<String> filteredTags = filterTags(priorityList, tags, mode); // Create a list of matching locales. List<Locale> filteredLocales = new ArrayList<>(filteredTags.size()); for (String tag : filteredTags) { filteredLocales.add(Locale.forLanguageTag(tag)); } return filteredLocales; } public static List<String> filterTags(List<LanguageRange> priorityList, Collection<String> tags, FilteringMode mode) { if (priorityList.isEmpty() || tags.isEmpty()) { return new ArrayList<>(); // need to return a empty mutable List } ArrayList<LanguageRange> list; if (mode == EXTENDED_FILTERING) { return filterExtended(priorityList, tags); } else { list = new ArrayList<>(); for (LanguageRange lr : priorityList) { String range = lr.getRange(); if (range.startsWith("*-") || range.indexOf("-*") != -1) { // Extended range if (mode == AUTOSELECT_FILTERING) { return filterExtended(priorityList, tags); } else if (mode == MAP_EXTENDED_RANGES) { if (range.charAt(0) == '*') { range = "*"; } else { range = range.replaceAll("-[*]", ""); } list.add(new LanguageRange(range, lr.getWeight())); } else if (mode == REJECT_EXTENDED_RANGES) { throw new IllegalArgumentException("An extended range \"" + range + "\" found in REJECT_EXTENDED_RANGES mode."); } } else { // Basic range list.add(lr); } } return filterBasic(list, tags); } } private static List<String> filterBasic(List<LanguageRange> priorityList, Collection<String> tags) { List<String> list = new ArrayList<>(); for (LanguageRange lr : priorityList) { String range = lr.getRange(); if (range.equals("*")) { return new ArrayList<String>(tags); } else { for (String tag : tags) { tag = tag.toLowerCase(); if (tag.startsWith(range)) { int len = range.length(); if ((tag.length() == len || tag.charAt(len) == '-') && !list.contains(tag)) { list.add(tag); } } } } } return list; } private static List<String> filterExtended(List<LanguageRange> priorityList, Collection<String> tags) { List<String> list = new ArrayList<>(); for (LanguageRange lr : priorityList) { String range = lr.getRange(); if (range.equals("*")) { return new ArrayList<String>(tags); } String[] rangeSubtags = range.split("-"); for (String tag : tags) { tag = tag.toLowerCase(); String[] tagSubtags = tag.split("-"); if (!rangeSubtags[0].equals(tagSubtags[0]) && !rangeSubtags[0].equals("*")) { continue; } int rangeIndex = 1; int tagIndex = 1; while (rangeIndex < rangeSubtags.length && tagIndex < tagSubtags.length) { if (rangeSubtags[rangeIndex].equals("*")) { rangeIndex++; } else if (rangeSubtags[rangeIndex].equals(tagSubtags[tagIndex])) { rangeIndex++; tagIndex++; } else if (tagSubtags[tagIndex].length() == 1 && !tagSubtags[tagIndex].equals("*")) { break; } else { tagIndex++; } } if (rangeSubtags.length == rangeIndex && !list.contains(tag)) { list.add(tag); } } } return list; } public static Locale lookup(List<LanguageRange> priorityList, Collection<Locale> locales) { if (priorityList.isEmpty() || locales.isEmpty()) { return null; } // Create a list of language tags to be matched. List<String> tags = new ArrayList<>(); for (Locale locale : locales) { tags.add(locale.toLanguageTag()); } // Look up a language tags. String lookedUpTag = lookupTag(priorityList, tags); if (lookedUpTag == null) { return null; } else { return Locale.forLanguageTag(lookedUpTag); } } public static String lookupTag(List<LanguageRange> priorityList, Collection<String> tags) { if (priorityList.isEmpty() || tags.isEmpty()) { return null; } for (LanguageRange lr : priorityList) { String range = lr.getRange(); // Special language range ("*") is ignored in lookup. if (range.equals("*")) { continue; } String rangeForRegex = range.replaceAll("\\x2A", "\\\\p{Alnum}*"); while (rangeForRegex.length() > 0) { for (String tag : tags) { tag = tag.toLowerCase(); if (tag.matches(rangeForRegex)) { return tag; } } // Truncate from the end.... int index = rangeForRegex.lastIndexOf('-'); if (index >= 0) { rangeForRegex = rangeForRegex.substring(0, index); // if range ends with an extension key, truncate it. if (rangeForRegex.lastIndexOf('-') == rangeForRegex.length()-2) { rangeForRegex = rangeForRegex.substring(0, rangeForRegex.length()-2); } } else { rangeForRegex = ""; } } } return null; } public static List<LanguageRange> parse(String ranges) { ranges = ranges.replaceAll(" ", "").toLowerCase(); if (ranges.startsWith("accept-language:")) { ranges = ranges.substring(16); // delete unnecessary prefix } String[] langRanges = ranges.split(","); List<LanguageRange> list = new ArrayList<>(langRanges.length); List<String> tempList = new ArrayList<>(); int numOfRanges = 0; for (String range : langRanges) { int index; String r; double w; if ((index = range.indexOf(";q=")) == -1) { r = range; w = MAX_WEIGHT; } else { r = range.substring(0, index); index += 3; try { w = Double.parseDouble(range.substring(index)); } catch (Exception e) { throw new IllegalArgumentException("weight=\"" + range.substring(index) + "\" for language range \"" + r + "\""); } if (w < MIN_WEIGHT || w > MAX_WEIGHT) { throw new IllegalArgumentException("weight=" + w + " for language range \"" + r + "\". It must be between " + MIN_WEIGHT + " and " + MAX_WEIGHT + "."); } } if (!tempList.contains(r)) { LanguageRange lr = new LanguageRange(r, w); index = numOfRanges; for (int j = 0; j < numOfRanges; j++) { if (list.get(j).getWeight() < w) { index = j; break; } } list.add(index, lr); numOfRanges++; tempList.add(r); // Check if the range has an equivalent using IANA LSR data. // If yes, add it to the User's Language Priority List as well. // aa-XX -> aa-YY String equivalent; if ((equivalent = getEquivalentForRegionAndVariant(r)) != null && !tempList.contains(equivalent)) { list.add(index+1, new LanguageRange(equivalent, w)); numOfRanges++; tempList.add(equivalent); } String[] equivalents; if ((equivalents = getEquivalentsForLanguage(r)) != null) { for (String equiv: equivalents) { // aa-XX -> bb-XX(, cc-XX) if (!tempList.contains(equiv)) { list.add(index+1, new LanguageRange(equiv, w)); numOfRanges++; tempList.add(equiv); } // bb-XX -> bb-YY(, cc-YY) equivalent = getEquivalentForRegionAndVariant(equiv); if (equivalent != null && !tempList.contains(equivalent)) { list.add(index+1, new LanguageRange(equivalent, w)); numOfRanges++; tempList.add(equivalent); } } } } } return list; } private static String[] getEquivalentsForLanguage(String range) { String r = range; while (r.length() > 0) { if (LocaleEquivalentMaps.singleEquivMap.containsKey(r)) { String equiv = LocaleEquivalentMaps.singleEquivMap.get(r); // Return immediately for performance if the first matching // subtag is found. return new String[] {range.replaceFirst(r, equiv)}; } else if (LocaleEquivalentMaps.multiEquivsMap.containsKey(r)) { String[] equivs = LocaleEquivalentMaps.multiEquivsMap.get(r); for (int i = 0; i < equivs.length; i++) { equivs[i] = range.replaceFirst(r, equivs[i]); } return equivs; } // Truncate the last subtag simply. int index = r.lastIndexOf('-'); if (index == -1) { break; } r = r.substring(0, index); } return null; } private static String getEquivalentForRegionAndVariant(String range) { int extensionKeyIndex = getExtentionKeyIndex(range); for (String subtag : LocaleEquivalentMaps.regionVariantEquivMap.keySet()) { int index; if ((index = range.indexOf(subtag)) != -1) { // Check if the matching text is a valid region or variant. if (extensionKeyIndex != Integer.MIN_VALUE && index > extensionKeyIndex) { continue; } int len = index + subtag.length(); if (range.length() == len || range.charAt(len) == '-') { return range.replaceFirst(subtag, LocaleEquivalentMaps.regionVariantEquivMap.get(subtag)); } } } return null; } private static int getExtentionKeyIndex(String s) { char[] c = s.toCharArray(); int index = Integer.MIN_VALUE; for (int i = 1; i < c.length; i++) { if (c[i] == '-') { if (i - index == 2) { return index; } else { index = i; } } } return Integer.MIN_VALUE; } public static List<LanguageRange> mapEquivalents( List<LanguageRange>priorityList, Map<String, List<String>> map) { if (priorityList.isEmpty()) { return new ArrayList<>(); // need to return a empty mutable List } if (map == null || map.isEmpty()) { return new ArrayList<LanguageRange>(priorityList); } // Create a map, key=originalKey.toLowerCaes(), value=originalKey Map<String, String> keyMap = new HashMap<>(); for (String key : map.keySet()) { keyMap.put(key.toLowerCase(), key); } List<LanguageRange> list = new ArrayList<>(); for (LanguageRange lr : priorityList) { String range = lr.getRange(); String r = range; boolean hasEquivalent = false; while (r.length() > 0) { if (keyMap.containsKey(r)) { hasEquivalent = true; List<String> equivalents = map.get(keyMap.get(r)); if (equivalents != null) { int len = r.length(); for (String equivalent : equivalents) { list.add(new LanguageRange(equivalent.toLowerCase() + range.substring(len), lr.getWeight())); } } // Return immediately if the first matching subtag is found. break; } // Truncate the last subtag simply. int index = r.lastIndexOf('-'); if (index == -1) { break; } r = r.substring(0, index); } if (!hasEquivalent) { list.add(lr); } } return list; } private LocaleMatcher() {} }