| /* GNU gettext for Java |
| * Copyright (C) 2001, 2007 Free Software Foundation, Inc. |
| * |
| * This program is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as published by |
| * the Free Software Foundation; either version 2.1 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this program. If not, see <https://www.gnu.org/licenses/>. |
| */ |
| |
| package gnu.gettext; |
| |
| import java.lang.reflect.*; |
| import java.util.*; |
| |
| /** |
| * This class implements the main GNU libintl functions in Java. |
| * <P> |
| * Using the GNU gettext approach, compiled message catalogs are normal |
| * Java ResourceBundle classes and are thus interoperable with standard |
| * ResourceBundle based code. |
| * <P> |
| * The main differences between the Sun ResourceBundle approach and the |
| * GNU gettext approach are: |
| * <UL> |
| * <LI>In the Sun approach, the keys are abstract textual shortcuts. |
| * In the GNU gettext approach, the keys are the English/ASCII version |
| * of the messages. |
| * <LI>In the Sun approach, the translation files are called |
| * "<VAR>Resource</VAR>_<VAR>locale</VAR>.properties" and have non-ASCII |
| * characters encoded in the Java |
| * <CODE>\</CODE><CODE>u<VAR>nnnn</VAR></CODE> syntax. Very few editors |
| * can natively display international characters in this format. In the |
| * GNU gettext approach, the translation files are called |
| * "<VAR>Resource</VAR>.<VAR>locale</VAR>.po" |
| * and are in the encoding the translator has chosen. Many editors |
| * can be used. There are at least three GUI translating tools |
| * (Emacs PO mode, KDE KBabel, GNOME gtranslator). |
| * <LI>In the Sun approach, the function |
| * <CODE>ResourceBundle.getString</CODE> throws a |
| * <CODE>MissingResourceException</CODE> when no translation is found. |
| * In the GNU gettext approach, the <CODE>gettext</CODE> function |
| * returns the (English) message key in that case. |
| * <LI>In the Sun approach, there is no support for plural handling. |
| * Even the most elaborate MessageFormat strings cannot provide decent |
| * plural handling. In the GNU gettext approach, we have the |
| * <CODE>ngettext</CODE> function. |
| * </UL> |
| * <P> |
| * To compile GNU gettext message catalogs into Java ResourceBundle classes, |
| * the <CODE>msgfmt</CODE> program can be used. |
| * |
| * @author Bruno Haible |
| */ |
| public abstract class GettextResource extends ResourceBundle { |
| |
| public static boolean verbose = false; |
| |
| /** |
| * Like gettext(catalog,msgid), except that it returns <CODE>null</CODE> |
| * when no translation was found. |
| */ |
| private static String gettextnull (ResourceBundle catalog, String msgid) { |
| try { |
| return (String)catalog.getObject(msgid); |
| } catch (MissingResourceException e) { |
| return null; |
| } |
| } |
| |
| /** |
| * Returns the translation of <VAR>msgid</VAR>. |
| * @param catalog a ResourceBundle |
| * @param msgid the key string to be translated, an ASCII string |
| * @return the translation of <VAR>msgid</VAR>, or <VAR>msgid</VAR> if |
| * none is found |
| */ |
| public static String gettext (ResourceBundle catalog, String msgid) { |
| String result = gettextnull(catalog,msgid); |
| if (result != null) |
| return result; |
| return msgid; |
| } |
| |
| /** |
| * Like ngettext(catalog,msgid,msgid_plural,n), except that it returns |
| * <CODE>null</CODE> when no translation was found. |
| */ |
| private static String ngettextnull (ResourceBundle catalog, String msgid, long n) { |
| // The reason why we use so many reflective API calls instead of letting |
| // the GNU gettext generated ResourceBundles implement some interface, |
| // is that we want the generated ResourceBundles to be completely |
| // standalone, so that migration from the Sun approach to the GNU gettext |
| // approach (without use of plurals) is as straightforward as possible. |
| ResourceBundle origCatalog = catalog; |
| do { |
| // Try catalog itself. |
| if (verbose) |
| System.out.println("ngettext on "+catalog); |
| Method handleGetObjectMethod = null; |
| Method getParentMethod = null; |
| try { |
| handleGetObjectMethod = catalog.getClass().getMethod("handleGetObject", new Class[] { java.lang.String.class }); |
| getParentMethod = catalog.getClass().getMethod("getParent", new Class[0]); |
| } catch (NoSuchMethodException e) { |
| } catch (SecurityException e) { |
| } |
| if (verbose) |
| System.out.println("handleGetObject = "+(handleGetObjectMethod!=null)+", getParent = "+(getParentMethod!=null)); |
| if (handleGetObjectMethod != null |
| && Modifier.isPublic(handleGetObjectMethod.getModifiers()) |
| && getParentMethod != null) { |
| // A GNU gettext created class. |
| Method lookupMethod = null; |
| Method pluralEvalMethod = null; |
| try { |
| lookupMethod = catalog.getClass().getMethod("lookup", new Class[] { java.lang.String.class }); |
| pluralEvalMethod = catalog.getClass().getMethod("pluralEval", new Class[] { Long.TYPE }); |
| } catch (NoSuchMethodException e) { |
| } catch (SecurityException e) { |
| } |
| if (verbose) |
| System.out.println("lookup = "+(lookupMethod!=null)+", pluralEval = "+(pluralEvalMethod!=null)); |
| if (lookupMethod != null && pluralEvalMethod != null) { |
| // A GNU gettext created class with plural handling. |
| Object localValue = null; |
| try { |
| localValue = lookupMethod.invoke(catalog, new Object[] { msgid }); |
| } catch (IllegalAccessException e) { |
| e.printStackTrace(); |
| } catch (InvocationTargetException e) { |
| e.getTargetException().printStackTrace(); |
| } |
| if (localValue != null) { |
| if (verbose) |
| System.out.println("localValue = "+localValue); |
| if (localValue instanceof String) |
| // Found the value. It doesn't depend on n in this case. |
| return (String)localValue; |
| else { |
| String[] pluralforms = (String[])localValue; |
| long i = 0; |
| try { |
| i = ((Long) pluralEvalMethod.invoke(catalog, new Object[] { new Long(n) })).longValue(); |
| if (!(i >= 0 && i < pluralforms.length)) |
| i = 0; |
| } catch (IllegalAccessException e) { |
| e.printStackTrace(); |
| } catch (InvocationTargetException e) { |
| e.getTargetException().printStackTrace(); |
| } |
| return pluralforms[(int)i]; |
| } |
| } |
| } else { |
| // A GNU gettext created class without plural handling. |
| Object localValue = null; |
| try { |
| localValue = handleGetObjectMethod.invoke(catalog, new Object[] { msgid }); |
| } catch (IllegalAccessException e) { |
| e.printStackTrace(); |
| } catch (InvocationTargetException e) { |
| e.getTargetException().printStackTrace(); |
| } |
| if (localValue != null) { |
| // Found the value. It doesn't depend on n in this case. |
| if (verbose) |
| System.out.println("localValue = "+localValue); |
| return (String)localValue; |
| } |
| } |
| Object parentCatalog = catalog; |
| try { |
| parentCatalog = getParentMethod.invoke(catalog, new Object[0]); |
| } catch (IllegalAccessException e) { |
| e.printStackTrace(); |
| } catch (InvocationTargetException e) { |
| e.getTargetException().printStackTrace(); |
| } |
| if (parentCatalog != catalog) |
| catalog = (ResourceBundle)parentCatalog; |
| else |
| break; |
| } else |
| // Not a GNU gettext created class. |
| break; |
| } while (catalog != null); |
| // The end of chain of GNU gettext ResourceBundles is reached. |
| if (catalog != null) { |
| // For a non-GNU ResourceBundle we cannot access 'parent' and |
| // 'handleGetObject', so make a single call to catalog and all |
| // its parent catalogs at once. |
| Object value; |
| try { |
| value = catalog.getObject(msgid); |
| } catch (MissingResourceException e) { |
| value = null; |
| } |
| if (value != null) |
| // Found the value. It doesn't depend on n in this case. |
| return (String)value; |
| } |
| // Default: null. |
| return null; |
| } |
| |
| /** |
| * Returns the plural form for <VAR>n</VAR> of the translation of |
| * <VAR>msgid</VAR>. |
| * @param catalog a ResourceBundle |
| * @param msgid the key string to be translated, an ASCII string |
| * @param msgid_plural its English plural form |
| * @return the translation of <VAR>msgid</VAR> depending on <VAR>n</VAR>, |
| * or <VAR>msgid</VAR> or <VAR>msgid_plural</VAR> if none is found |
| */ |
| public static String ngettext (ResourceBundle catalog, String msgid, String msgid_plural, long n) { |
| String result = ngettextnull(catalog,msgid,n); |
| if (result != null) |
| return result; |
| // Default: English strings and Germanic plural rule. |
| return (n != 1 ? msgid_plural : msgid); |
| } |
| |
| /* The separator between msgctxt and msgid. */ |
| private static final String CONTEXT_GLUE = "\u0004"; |
| |
| /** |
| * Returns the translation of <VAR>msgid</VAR> in the context of |
| * <VAR>msgctxt</VAR>. |
| * @param catalog a ResourceBundle |
| * @param msgctxt the context for the key string, an ASCII string |
| * @param msgid the key string to be translated, an ASCII string |
| * @return the translation of <VAR>msgid</VAR>, or <VAR>msgid</VAR> if |
| * none is found |
| */ |
| public static String pgettext (ResourceBundle catalog, String msgctxt, String msgid) { |
| String result = gettextnull(catalog,msgctxt+CONTEXT_GLUE+msgid); |
| if (result != null) |
| return result; |
| return msgid; |
| } |
| |
| /** |
| * Returns the plural form for <VAR>n</VAR> of the translation of |
| * <VAR>msgid</VAR> in the context of <VAR>msgctxt</VAR>. |
| * @param catalog a ResourceBundle |
| * @param msgctxt the context for the key string, an ASCII string |
| * @param msgid the key string to be translated, an ASCII string |
| * @param msgid_plural its English plural form |
| * @return the translation of <VAR>msgid</VAR> depending on <VAR>n</VAR>, |
| * or <VAR>msgid</VAR> or <VAR>msgid_plural</VAR> if none is found |
| */ |
| public static String npgettext (ResourceBundle catalog, String msgctxt, String msgid, String msgid_plural, long n) { |
| String result = ngettextnull(catalog,msgctxt+CONTEXT_GLUE+msgid,n); |
| if (result != null) |
| return result; |
| // Default: English strings and Germanic plural rule. |
| return (n != 1 ? msgid_plural : msgid); |
| } |
| } |
