1/* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package androidx.core.text; 18 19import android.os.Build; 20import android.util.Log; 21 22import androidx.annotation.Nullable; 23 24import java.lang.reflect.InvocationTargetException; 25import java.lang.reflect.Method; 26import java.util.Locale; 27 28public final class ICUCompat { 29 private static final String TAG = "ICUCompat"; 30 31 private static Method sGetScriptMethod; 32 private static Method sAddLikelySubtagsMethod; 33 34 static { 35 if (Build.VERSION.SDK_INT >= 21) { 36 try { 37 // This class should always exist on API-21 since it's CTS tested. 38 final Class<?> clazz = Class.forName("libcore.icu.ICU"); 39 sAddLikelySubtagsMethod = clazz.getMethod("addLikelySubtags", 40 new Class[]{ Locale.class }); 41 } catch (Exception e) { 42 throw new IllegalStateException(e); 43 } 44 } else { 45 try { 46 final Class<?> clazz = Class.forName("libcore.icu.ICU"); 47 if (clazz != null) { 48 sGetScriptMethod = clazz.getMethod("getScript", 49 new Class[]{ String.class }); 50 sAddLikelySubtagsMethod = clazz.getMethod("addLikelySubtags", 51 new Class[]{ String.class }); 52 } 53 } catch (Exception e) { 54 sGetScriptMethod = null; 55 sAddLikelySubtagsMethod = null; 56 57 // Nothing we can do here, we just log the exception 58 Log.w(TAG, e); 59 } 60 } 61 } 62 63 /** 64 * Returns the script for a given Locale. 65 * 66 * If the locale isn't already in its maximal form, likely subtags for the provided locale 67 * ID are added before we determine the script. For further details, see the following CLDR 68 * technical report : 69 * 70 * http://www.unicode.org/reports/tr35/#Likely_Subtags 71 * 72 * If locale is already in the maximal form, or there is no data available for maximization, 73 * it will be just returned. For example, "und-Zzzz" cannot be maximized, since there is no 74 * reasonable maximization. 75 * 76 * Examples: 77 * 78 * "en" maximizes to "en_Latn_US" 79 * "de" maximizes to "de_Latn_US" 80 * "sr" maximizes to "sr_Cyrl_RS" 81 * "sh" maximizes to "sr_Latn_RS" (Note this will not reverse.) 82 * "zh_Hani" maximizes to "zh_Hans_CN" (Note this will not reverse.) 83 * 84 * @return The script for a given Locale if ICU library is available, otherwise null. 85 */ 86 @Nullable 87 public static String maximizeAndGetScript(Locale locale) { 88 if (Build.VERSION.SDK_INT >= 21) { 89 try { 90 final Object[] args = new Object[] { locale }; 91 return ((Locale) sAddLikelySubtagsMethod.invoke(null, args)).getScript(); 92 } catch (InvocationTargetException e) { 93 Log.w(TAG, e); 94 } catch (IllegalAccessException e) { 95 Log.w(TAG, e); 96 } 97 return locale.getScript(); 98 } else { 99 final String localeWithSubtags = addLikelySubtags(locale); 100 if (localeWithSubtags != null) { 101 return getScript(localeWithSubtags); 102 } 103 104 return null; 105 } 106 } 107 108 private static String getScript(String localeStr) { 109 try { 110 if (sGetScriptMethod != null) { 111 final Object[] args = new Object[] { localeStr }; 112 return (String) sGetScriptMethod.invoke(null, args); 113 } 114 } catch (IllegalAccessException e) { 115 // Nothing we can do here, we just log the exception 116 Log.w(TAG, e); 117 } catch (InvocationTargetException e) { 118 // Nothing we can do here, we just log the exception 119 Log.w(TAG, e); 120 } 121 return null; 122 } 123 124 private static String addLikelySubtags(Locale locale) { 125 final String localeStr = locale.toString(); 126 try { 127 if (sAddLikelySubtagsMethod != null) { 128 final Object[] args = new Object[] { localeStr }; 129 return (String) sAddLikelySubtagsMethod.invoke(null, args); 130 } 131 } catch (IllegalAccessException e) { 132 // Nothing we can do here, we just log the exception 133 Log.w(TAG, e); 134 } catch (InvocationTargetException e) { 135 // Nothing we can do here, we just log the exception 136 Log.w(TAG, e); 137 } 138 139 return localeStr; 140 } 141 142 private ICUCompat() {} 143} 144