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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed 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.
*/
import java.util.Locale;
import java.util.TreeMap;
/**
* A class to help with handling different writing scripts.
*/
public class ScriptUtils {
// Used for hardware keyboards
public static final int SCRIPT_UNKNOWN = -1;
public static final int SCRIPT_ARABIC = 0;
public static final int SCRIPT_ARMENIAN = 1;
public static final int SCRIPT_BENGALI = 2;
public static final int SCRIPT_CYRILLIC = 3;
public static final int SCRIPT_DEVANAGARI = 4;
public static final int SCRIPT_GEORGIAN = 5;
public static final int SCRIPT_GREEK = 6;
public static final int SCRIPT_HEBREW = 7;
public static final int SCRIPT_KANNADA = 8;
public static final int SCRIPT_KHMER = 9;
public static final int SCRIPT_LAO = 10;
public static final int SCRIPT_LATIN = 11;
public static final int SCRIPT_MALAYALAM = 12;
public static final int SCRIPT_MYANMAR = 13;
public static final int SCRIPT_SINHALA = 14;
public static final int SCRIPT_TAMIL = 15;
public static final int SCRIPT_TELUGU = 16;
public static final int SCRIPT_THAI = 17;
private static final TreeMap<String, Integer> mLanguageCodeToScriptCode;
mLanguageCodeToScriptCode = new TreeMap<>();
mLanguageCodeToScriptCode.put("", SCRIPT_LATIN); // default
mLanguageCodeToScriptCode.put("ar", SCRIPT_ARABIC);
mLanguageCodeToScriptCode.put("hy", SCRIPT_ARMENIAN);
mLanguageCodeToScriptCode.put("bn", SCRIPT_BENGALI);
mLanguageCodeToScriptCode.put("bg", SCRIPT_CYRILLIC);
mLanguageCodeToScriptCode.put("sr", SCRIPT_CYRILLIC);
mLanguageCodeToScriptCode.put("ru", SCRIPT_CYRILLIC);
mLanguageCodeToScriptCode.put("ka", SCRIPT_GEORGIAN);
mLanguageCodeToScriptCode.put("el", SCRIPT_GREEK);
mLanguageCodeToScriptCode.put("iw", SCRIPT_HEBREW);
mLanguageCodeToScriptCode.put("km", SCRIPT_KHMER);
mLanguageCodeToScriptCode.put("lo", SCRIPT_LAO);
mLanguageCodeToScriptCode.put("ml", SCRIPT_MALAYALAM);
mLanguageCodeToScriptCode.put("my", SCRIPT_MYANMAR);
mLanguageCodeToScriptCode.put("si", SCRIPT_SINHALA);
mLanguageCodeToScriptCode.put("ta", SCRIPT_TAMIL);
mLanguageCodeToScriptCode.put("te", SCRIPT_TELUGU);
mLanguageCodeToScriptCode.put("th", SCRIPT_THAI);
/*
* Returns whether the code point is a letter that makes sense for the specified
* locale for this spell checker.
* The dictionaries supported by Latin IME are described in res/xml/spellchecker.xml
* and is limited to EFIGS languages and Russian.
* Hence at the moment this explicitly tests for Cyrillic characters or Latin characters
* as appropriate, and explicitly excludes CJK, Arabic and Hebrew characters.
*/
public static boolean isLetterPartOfScript(final int codePoint, final int scriptId) {
switch (scriptId) {
case SCRIPT_ARABIC:
// Arabic letters can be in any of the following blocks:
// Arabic U+0600..U+06FF
// Arabic Supplement, Thaana U+0750..U+077F, U+0780..U+07BF
// Arabic Extended-A U+08A0..U+08FF
// Arabic Presentation Forms-A U+FB50..U+FDFF
// Arabic Presentation Forms-B U+FE70..U+FEFF
return (codePoint >= 0x600 && codePoint <= 0x6FF)
|| (codePoint >= 0x750 && codePoint <= 0x7BF)
|| (codePoint >= 0x8A0 && codePoint <= 0x8FF)
|| (codePoint >= 0xFB50 && codePoint <= 0xFDFF)
|| (codePoint >= 0xFE70 && codePoint <= 0xFEFF);
case SCRIPT_ARMENIAN:
// Armenian letters are in the Armenian unicode block, U+0530..U+058F and
// Alphabetic Presentation Forms block, U+FB00..U+FB4F, but only in the Armenian part
// of that block, which is U+FB13..U+FB17.
return (codePoint >= 0x530 && codePoint <= 0x58F
|| codePoint >= 0xFB13 && codePoint <= 0xFB17);
case SCRIPT_BENGALI:
// Bengali unicode block is U+0980..U+09FF
return (codePoint >= 0x980 && codePoint <= 0x9FF);
case SCRIPT_CYRILLIC:
// All Cyrillic characters are in the 400~52F block. There are some in the upper
// Unicode range, but they are archaic characters that are not used in modern
// Russian and are not used by our dictionary.
return codePoint >= 0x400 && codePoint <= 0x52F && Character.isLetter(codePoint);
case SCRIPT_DEVANAGARI:
// Devanagari unicode block is +0900..U+097F
return (codePoint >= 0x900 && codePoint <= 0x97F);
case SCRIPT_GEORGIAN:
// Georgian letters are in the Georgian unicode block, U+10A0..U+10FF,
// or Georgian supplement block, U+2D00..U+2D2F
return (codePoint >= 0x10A0 && codePoint <= 0x10FF
|| codePoint >= 0x2D00 && codePoint <= 0x2D2F);
case SCRIPT_GREEK:
// Greek letters are either in the 370~3FF range (Greek & Coptic), or in the
// 1F00~1FFF range (Greek extended). Our dictionary contains both sort of characters.
// Our dictionary also contains a few words with 0xF2; it would be best to check
// if that's correct, but a web search does return results for these words so
// they are probably okay.
return (codePoint >= 0x370 && codePoint <= 0x3FF)
|| (codePoint >= 0x1F00 && codePoint <= 0x1FFF)
|| codePoint == 0xF2;
case SCRIPT_HEBREW:
// Hebrew letters are in the Hebrew unicode block, which spans from U+0590 to U+05FF,
// or in the Alphabetic Presentation Forms block, U+FB00..U+FB4F, but only in the
// Hebrew part of that block, which is U+FB1D..U+FB4F.
return (codePoint >= 0x590 && codePoint <= 0x5FF
|| codePoint >= 0xFB1D && codePoint <= 0xFB4F);
case SCRIPT_KANNADA:
// Kannada unicode block is U+0C80..U+0CFF
return (codePoint >= 0xC80 && codePoint <= 0xCFF);
case SCRIPT_KHMER:
// Khmer letters are in unicode block U+1780..U+17FF, and the Khmer symbols block
// is U+19E0..U+19FF
return (codePoint >= 0x1780 && codePoint <= 0x17FF
|| codePoint >= 0x19E0 && codePoint <= 0x19FF);
case SCRIPT_LAO:
// The Lao block is U+0E80..U+0EFF
return (codePoint >= 0xE80 && codePoint <= 0xEFF);
case SCRIPT_LATIN:
// Our supported latin script dictionaries (EFIGS) at the moment only include
// characters in the C0, C1, Latin Extended A and B, IPA extensions unicode
// blocks. As it happens, those are back-to-back in the code range 0x40 to 0x2AF,
// so the below is a very efficient way to test for it. As for the 0-0x3F, it's
// excluded from isLetter anyway.
return codePoint <= 0x2AF && Character.isLetter(codePoint);
case SCRIPT_MALAYALAM:
// Malayalam unicode block is U+0D00..U+0D7F
return (codePoint >= 0xD00 && codePoint <= 0xD7F);
case SCRIPT_MYANMAR:
// Myanmar has three unicode blocks :
// Myanmar U+1000..U+109F
// Myanmar extended-A U+AA60..U+AA7F
// Myanmar extended-B U+A9E0..U+A9FF
return (codePoint >= 0x1000 && codePoint <= 0x109F
|| codePoint >= 0xAA60 && codePoint <= 0xAA7F
|| codePoint >= 0xA9E0 && codePoint <= 0xA9FF);
case SCRIPT_SINHALA:
// Sinhala unicode block is U+0D80..U+0DFF
return (codePoint >= 0xD80 && codePoint <= 0xDFF);
case SCRIPT_TAMIL:
// Tamil unicode block is U+0B80..U+0BFF
return (codePoint >= 0xB80 && codePoint <= 0xBFF);
case SCRIPT_TELUGU:
// Telugu unicode block is U+0C00..U+0C7F
return (codePoint >= 0xC00 && codePoint <= 0xC7F);
case SCRIPT_THAI:
// Thai unicode block is U+0E00..U+0E7F
return (codePoint >= 0xE00 && codePoint <= 0xE7F);
case SCRIPT_UNKNOWN:
return true;
default:
// Should never come here
throw new RuntimeException("Impossible value of script: " + scriptId);
/**
* @param locale spell checker locale
* @return internal Latin IME script code that maps to a language code
* {@see http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes}
public static int getScriptFromSpellCheckerLocale(final Locale locale) {
String language = locale.getLanguage();
Integer script = mLanguageCodeToScriptCode.get(language);
if (script == null) {
// Default to Latin.
script = mLanguageCodeToScriptCode.get("");