Java tutorial
/* * Copyright 2005,2006 WSO2, Inc. http://www.wso2.org * * 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. */ package org.wso2.carbon.utils.i18n; import java.io.IOException; import java.io.InputStream; import java.text.MessageFormat; import java.util.Enumeration; import java.util.Hashtable; import java.util.Locale; import java.util.MissingResourceException; import java.util.Properties; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * CURRENTLY NOT USED * KEEPING FOR REFERENCE 9/19/2002 * <p/> * <p>Wrapper class for resource bundles. Property files are used to store * resource strings, which are the only types of resources available. * Property files can inherit properties from other files so that * a base property file can be used and a small number of properties * can be over-ridden by another property file. For example you may * create an english version of a resource file named "resource.properties". * You then decide that the British English version of all of the properties * except one are the same, so there is no need to redefine all of the * properties in "resource_en_GB", just the one that is different.</p> * <p>The property file lookup searches for classes with various suffixes * on the basis if the desired local and the current default local * (as returned by Local.getDefault()). As property files are found the * property values are merged so that inheritance is preserved.</p> * <p>The order of searching is:</p> * <dir> * basename + "_" + langage + "_" + country + "_" + variant * basename + "_" + langage + "_" + country * basename + "_" + langage * basename + "_" + defaultLanguage + "_" + defaultCountry + "_" + defaultVariant * basename + "_" + defaultLanguage + "_" + defaultCountry * basename + "_" + defaultLanguage * basename * </dir> * <p>The basename is the name of the property file without the ".properties" * extension.</p> * <p>Properties will be cached for performance.<p> * <p>Property values stored in the property files can also contain dynamic * variables. Any dynamic variable defined in PropertiesUtil.getVariableValue() * can be used (such as {date}), as well as arguments in the form {0}, {1}, etc. * Argument values are specified in the various overloaded getString() methods.</p> */ public class ResourceBundle { private static Log log = LogFactory.getLog(ResourceBundle.class); // The static cache of properties. The key is the basename + the local + // the default local and the element is the Properties object containing // the resources private static Hashtable propertyCache = new Hashtable(); // The default base name public static final String BASE_NAME = "resource"; // The property file extension public static final String PROPERTY_EXT = ".properties"; // The name of the current base property file (with extension) protected String basePropertyFileName; // The properties for the current resource bundle protected Properties resourceProperties; /** * Construct a new RB * * @param name The name of the property file without the ".properties" extension */ public ResourceBundle(String name) { this(null, name, null); } /** * Construct a new RB * * @param caller The calling object. This is used to get the package name * to further construct the basename as well as to get the proper ClassLoader * @param name The name of the property file without the ".properties" extension */ public ResourceBundle(Object caller, String name) { this(caller, name, null); } /** * Construct a new RB * * @param caller The calling object. This is used to get the package name * to further construct the basename as well as to get the proper ClassLoader * @param name The name of the property file without the ".properties" extension * @param locale The locale */ public ResourceBundle(Object caller, String name, Locale locale) { ClassLoader cl = null; if (caller != null) { Class c; if (caller instanceof Class) { c = (Class) caller; } else { c = caller.getClass(); } // Get the appropriate class loader cl = c.getClassLoader(); if (name.indexOf('/') == -1) { // Create the full basename only if not given String fullName = c.getName(); int pos = fullName.lastIndexOf('.'); if (pos > 0) { name = fullName.substring(0, pos + 1).replace('.', '/') + name; } } } else { // Try the shared default properties file... if (name.indexOf('/') == -1) { name = "org/apache/axis/default-resource"; } } Locale defaultLocale = Locale.getDefault(); // If the locale given is the same as the default locale, ignore it if (locale != null && locale.equals(defaultLocale)) { locale = null; } // Load the properties. If no property files exist then a // MissingResourceException will be thrown loadProperties(name, cl, locale, defaultLocale); } /** * Gets a string message from the resource bundle for the given key * * @param key The resource key * @return The message */ public String getString(String key) { return getString(key, (Object[]) null); } /** * <p>Gets a string message from the resource bundle for the given key. The * message may contain variables that will be substituted with the given * arguments. Variables have the format:</p> * <dir> * This message has two variables: {0} and {1} * </dir> * * @param key The resource key * @param arg0 The argument to place in variable {0} * @return The message */ public String getString(String key, Object arg0) { Object[] o = new Object[1]; o[0] = arg0; return getString(key, o); } /** * <p>Gets a string message from the resource bundle for the given key. The * message may contain variables that will be substituted with the given * arguments. Variables have the format:</p> * <dir> * This message has two variables: {0} and {1} * </dir> * * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @return The message */ public String getString(String key, Object arg0, Object arg1) { Object[] o = new Object[2]; o[0] = arg0; o[1] = arg1; return getString(key, o); } /** * <p>Gets a string message from the resource bundle for the given key. The * message may contain variables that will be substituted with the given * arguments. Variables have the format:</p> * <dir> * This message has two variables: {0} and {1} * </dir> * * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {1} * @return The message */ public String getString(String key, Object arg0, Object arg1, Object arg2) { Object[] o = new Object[3]; o[0] = arg0; o[1] = arg1; o[2] = arg2; return getString(key, o); } /** * <p>Gets a string message from the resource bundle for the given key. The * message may contain variables that will be substituted with the given * arguments. Variables have the format:</p> * <dir> * This message has two variables: {0} and {1} * </dir> * * @param key The resource key * @param array An array of objects to place in corresponding variables * @return The message */ public String getString(String key, Object[] array) { String msg = null; if (resourceProperties != null) { msg = resourceProperties.getProperty(key); } if (msg == null) { throw new MissingResourceException( "Cannot find resource key \"" + key + "\" in base name " + basePropertyFileName, basePropertyFileName, key); } msg = MessageFormat.format(msg, array); return msg; } protected void loadProperties(String basename, ClassLoader loader, Locale locale, Locale defaultLocale) { // Check the cache first String loaderName = ""; if (loader != null) { loaderName = ":" + loader.hashCode(); } String cacheKey = basename + ":" + locale + ":" + defaultLocale + loaderName; Properties p = (Properties) propertyCache.get(cacheKey); basePropertyFileName = basename + PROPERTY_EXT; if (p == null) { // The properties were not found in the cache. Search the given locale first p = new Properties(); if (locale != null) { p = loadProperties(basename, loader, locale, p); } // Search the default locale if (defaultLocale != null) { p = loadProperties(basename, loader, defaultLocale, p); } // Search for the basename p = merge(p, loadProperties(basePropertyFileName, loader)); if (p == null) { throw new MissingResourceException("Cannot find resource for base name " + basePropertyFileName, basePropertyFileName, ""); } // Cache the properties propertyCache.put(cacheKey, p); } resourceProperties = p; } protected Properties loadProperties(String basename, ClassLoader loader, Locale locale, Properties props) { String language = locale.getLanguage(); String country = locale.getCountry(); String variant = locale.getVariant(); if (variant != null && variant.trim().length() == 0) { variant = null; } if (language != null) { if (country != null) { if (variant != null) { props = merge(props, loadProperties( basename + "_" + language + "_" + country + "_" + variant + PROPERTY_EXT, loader)); } props = merge(props, loadProperties(basename + "_" + language + "_" + country + PROPERTY_EXT, loader)); } props = merge(props, loadProperties(basename + "_" + language + PROPERTY_EXT, loader)); } return props; } protected Properties loadProperties(String resname, ClassLoader loader) { Properties props = null; // Attempt to open and load the properties InputStream in = null; try { if (loader != null) { in = loader.getResourceAsStream(resname); } // Either we're using the system class loader or we didn't find the // resource using the given class loader if (in == null) { in = ClassLoader.getSystemResourceAsStream(resname); } if (in != null) { props = new Properties(); try { props.load(in); } catch (IOException ex) { // On error, clear the props props = null; } } } finally { if (in != null) { try { in.close(); } catch (Exception ex) { // Ignore error on close if (log.isDebugEnabled()) { log.debug("Error closing input stream", ex); } } } } return props; } /** * Merge two Properties objects */ protected Properties merge(Properties p1, Properties p2) { if ((p1 == null) && (p2 == null)) { return null; } else if (p1 == null) { return p2; } else if (p2 == null) { return p1; } // Now merge. p1 takes precedence Enumeration enumeration = p2.keys(); while (enumeration.hasMoreElements()) { String key = (String) enumeration.nextElement(); if (p1.getProperty(key) == null) { p1.put(key, p2.getProperty(key)); } } return p1; } /** * Get the underlying properties */ public Properties getProperties() { return resourceProperties; } // STATIC ACCESSORS /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @return The formatted message */ public static String getString(Object caller, String key) { return getMessage(caller, BASE_NAME, null, key, null); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param arg0 The argument to place in variable {0} * @return The formatted message */ public static String getString(Object caller, String key, Object arg0) { Object[] o = new Object[1]; o[0] = arg0; return getMessage(caller, BASE_NAME, null, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @return The formatted message */ public static String getString(Object caller, String key, Object arg0, Object arg1) { Object[] o = new Object[2]; o[0] = arg0; o[1] = arg1; return getMessage(caller, BASE_NAME, null, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @return The formatted message */ public static String getString(Object caller, String key, Object arg0, Object arg1, Object arg2) { Object[] o = new Object[3]; o[0] = arg0; o[1] = arg1; o[2] = arg2; return getMessage(caller, BASE_NAME, null, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @param arg3 The argument to place in variable {3} * @return The formatted message */ public static String getString(Object caller, String key, Object arg0, Object arg1, Object arg2, Object arg3) { Object[] o = new Object[4]; o[0] = arg0; o[1] = arg1; o[2] = arg2; o[3] = arg3; return getMessage(caller, BASE_NAME, null, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @param arg3 The argument to place in variable {3} * @param arg4 The argument to place in variable {4} * @return Returns the formatted message. */ public static String getString(Object caller, String key, Object arg0, Object arg1, Object arg2, Object arg3, Object arg4) { Object[] o = new Object[5]; o[0] = arg0; o[1] = arg1; o[2] = arg2; o[3] = arg3; o[4] = arg4; return getMessage(caller, BASE_NAME, null, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param key The resource key * @param args An array of objects to place in corresponding variables * @return Returns the formatted message. */ public static String getString(Object caller, String key, Object[] args) { return getMessage(caller, BASE_NAME, null, key, args); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @return The formatted message */ public static String getString(Object caller, Locale locale, String key) { return getMessage(caller, BASE_NAME, locale, key, null); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param arg0 The argument to place in variable {0} * @return The formatted message */ public static String getString(Object caller, Locale locale, String key, Object arg0) { Object[] o = new Object[1]; o[0] = arg0; return getMessage(caller, BASE_NAME, locale, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @return The formatted message */ public static String getString(Object caller, Locale locale, String key, Object arg0, Object arg1) { Object[] o = new Object[2]; o[0] = arg0; o[1] = arg1; return getMessage(caller, BASE_NAME, locale, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @return The formatted message */ public static String getString(Object caller, Locale locale, String key, Object arg0, Object arg1, Object arg2) { Object[] o = new Object[3]; o[0] = arg0; o[1] = arg1; o[2] = arg2; return getMessage(caller, BASE_NAME, locale, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @param arg3 The argument to place in variable {3} * @return The formatted message */ public static String getString(Object caller, Locale locale, String key, Object arg0, Object arg1, Object arg2, Object arg3) { Object[] o = new Object[4]; o[0] = arg0; o[1] = arg1; o[2] = arg2; o[3] = arg3; return getMessage(caller, BASE_NAME, locale, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param arg0 The argument to place in variable {0} * @param arg1 The argument to place in variable {1} * @param arg2 The argument to place in variable {2} * @param arg3 The argument to place in variable {3} * @return Returns the formatted message. */ public static String getString(Object caller, Locale locale, String key, Object arg0, Object arg1, Object arg2, Object arg3, Object arg4) { Object[] o = new Object[5]; o[0] = arg0; o[1] = arg1; o[2] = arg2; o[3] = arg3; o[4] = arg4; return getMessage(caller, BASE_NAME, locale, key, o); } /** * Get a message from resource.properties from the package of the given object. * * @param caller The calling object, used to get the package name and class loader * @param locale The locale * @param key The resource key * @param args An array of objects to place in corresponding variables * @return Returns the formatted message. */ public static String getString(Object caller, Locale locale, String key, Object[] args) { return getMessage(caller, BASE_NAME, locale, key, args); } // Workhorse that does the resource loading and key lookup public static String getMessage(Object caller, String basename, Locale locale, String key, Object[] args) { String msg = null; MissingResourceException firstEx = null; String fullName = null; Class curClass = null; boolean didNull = false; if (caller != null) { if (caller instanceof Class) { curClass = (Class) caller; } else { curClass = caller.getClass(); } } while (msg == null) { // Get the full name of the resource if (curClass != null) { // Create the full basename String pkgName = curClass.getName(); int pos = pkgName.lastIndexOf('.'); if (pos > 0) { fullName = pkgName.substring(0, pos + 1).replace('.', '/') + basename; } else { fullName = basename; } } else { fullName = basename; } try { ResourceBundle resourceBundle = new ResourceBundle(caller, fullName, locale); msg = resourceBundle.getString(key, args); } catch (MissingResourceException ex) { if (curClass == null) { throw ex; } // Save the first exception if (firstEx == null) { firstEx = ex; } // Get the superclass curClass = curClass.getSuperclass(); if (curClass == null) { if (didNull) { throw firstEx; } didNull = true; caller = null; } else { String cname = curClass.getName(); if (cname.startsWith("java.") || cname.startsWith("javax.")) { if (didNull) { throw firstEx; } didNull = true; caller = null; curClass = null; } } } } return msg; } /** * Clears the internal cache. */ public static void clearCache() { propertyCache.clear(); } }