Source code

001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2025 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
018///////////////////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle;
021
022import java.io.IOException;
023import java.io.InputStreamReader;
024import java.io.Reader;
025import java.net.URL;
026import java.net.URLConnection;
027import java.nio.charset.StandardCharsets;
028import java.text.MessageFormat;
029import java.util.Locale;
030import java.util.MissingResourceException;
031import java.util.PropertyResourceBundle;
032import java.util.ResourceBundle;
033import java.util.ResourceBundle.Control;
034
035import com.puppycrawl.tools.checkstyle.utils.UnmodifiableCollectionUtil;
036
037/**
038 * Represents a message that can be localised. The translations come from
039 * message.properties files. The underlying implementation uses
040 * java.text.MessageFormat.
041 */
042public class LocalizedMessage {
043
044 /** The locale to localise messages to. **/
045 private static Locale sLocale = Locale.getDefault();
046
047 /** Name of the resource bundle to get messages from. **/
048 private final String bundle;
049
050 /** Class of the source for this message. */
051 private final Class<?> sourceClass;
052
053 /**
054 * Key for the message format.
055 **/
056 private final String key;
057
058 /**
059 * Arguments for java.text.MessageFormat, that is why type is Object[].
060 *
061 * <p>Note: Changing types from Object[] will be huge breaking compatibility, as Module
062 * messages use some type formatting already, so better to keep it as Object[].
063 * </p>
064 */
065 private final Object[] args;
066
067 /**
068 * Creates a new {@code LocalizedMessage} instance.
069 *
070 * @param bundle resource bundle name
071 * @param sourceClass the Class that is the source of the message
072 * @param key the key to locate the translation.
073 * @param args arguments for the translation.
074 */
075 public LocalizedMessage(String bundle, Class<?> sourceClass, String key,
076 Object... args) {
077 this.bundle = bundle;
078 this.sourceClass = sourceClass;
079 this.key = key;
080 if (args == null) {
081 this.args = null;
082 }
083 else {
084 this.args = UnmodifiableCollectionUtil.copyOfArray(args, args.length);
085 }
086 }
087
088 /**
089 * Sets a locale to use for localization.
090 *
091 * @param locale the locale to use for localization
092 */
093 public static void setLocale(Locale locale) {
094 if (Locale.ENGLISH.getLanguage().equals(locale.getLanguage())) {
095 sLocale = Locale.ROOT;
096 }
097 else {
098 sLocale = locale;
099 }
100 }
101
102 /**
103 * Gets the translated message.
104 *
105 * @return the translated message.
106 */
107 public String getMessage() {
108 String result;
109 try {
110 // Important to use the default class loader, and not the one in
111 // the GlobalProperties object. This is because the class loader in
112 // the GlobalProperties is specified by the user for resolving
113 // custom classes.
114 final ResourceBundle resourceBundle = getBundle();
115 final String pattern = resourceBundle.getString(key);
116 final MessageFormat formatter = new MessageFormat(pattern, Locale.ROOT);
117 result = formatter.format(args);
118 }
119 catch (final MissingResourceException ignored) {
120 // If the Check author didn't provide i18n resource bundles
121 // and logs audit event messages directly, this will return
122 // the author's original message
123 final MessageFormat formatter = new MessageFormat(key, Locale.ROOT);
124 result = formatter.format(args);
125 }
126 return result;
127 }
128
129 /**
130 * Obtain the ResourceBundle. Uses the classloader
131 * of the class emitting this message, to be sure to get the correct
132 * bundle.
133 *
134 * @return a ResourceBundle.
135 */
136 private ResourceBundle getBundle() {
137 return ResourceBundle.getBundle(bundle, sLocale, sourceClass.getClassLoader(),
138 new Utf8Control());
139 }
140
141 /**
142 * Custom ResourceBundle.Control implementation which allows explicitly read
143 * the properties files as UTF-8.
144 */
145 public static class Utf8Control extends Control {
146
147 @Override
148 public ResourceBundle newBundle(String baseName, Locale locale, String format,
149 ClassLoader loader, boolean reload) throws IOException {
150 // The below is a copy of the default implementation.
151 final String bundleName = toBundleName(baseName, locale);
152 final String resourceName = toResourceName(bundleName, "properties");
153 final URL url = loader.getResource(resourceName);
154 ResourceBundle resourceBundle = null;
155 if (url != null) {
156 final URLConnection connection = url.openConnection();
157 if (connection != null) {
158 connection.setUseCaches(!reload);
159 try (Reader streamReader = new InputStreamReader(connection.getInputStream(),
160 StandardCharsets.UTF_8)) {
161 // Only this line is changed to make it read property files as UTF-8.
162 resourceBundle = new PropertyResourceBundle(streamReader);
163 }
164 }
165 }
166 return resourceBundle;
167 }
168
169 }
170
171}