src/org/apache/harmony/luni/util/MsgHelp.java

   1 /*
   2  *  Licensed to the Apache Software Foundation (ASF) under one or more
   3  *  contributor license agreements.  See the NOTICE file distributed with
   4  *  this work for additional information regarding copyright ownership.
   5  *  The ASF licenses this file to You under the Apache License, Version 2.0
   6  *  (the "License"); you may not use this file except in compliance with
   7  *  the License.  You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  *  Unless required by applicable law or agreed to in writing, software
  12  *  distributed under the License is distributed on an "AS IS" BASIS,
  13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  *  See the License for the specific language governing permissions and
  15  *  limitations under the License.
  16  */
  17
  18 package org.apache.harmony.luni.util;
  19
  20 /**
  21  * This class contains helper methods for loading resource bundles and
  22  * formatting external message strings.
  23  *
  24  */
  25
  26 public final class MsgHelp {
  27
  28         /**
  29          * Generates a formatted text string given a source string containing
  30          * "argument markers" of the form "{argNum}" where each argNum must be in
  31          * the range 0..9. The result is generated by inserting the toString of each
  32          * argument into the position indicated in the string.
  33          * <p>
  34          * To insert the "{" character into the output, use a single backslash
  35          * character to escape it (i.e. "\{"). The "}" character does not need to be
  36          * escaped.
  37          *
  38          * @param format
  39          *            String the format to use when printing.
  40          * @param args
  41          *            Object[] the arguments to use.
  42          * @return String the formatted message.
  43          */
  44         public static String format(String format, Object[] args) {
  45                 StringBuilder answer = new StringBuilder(format.length()
  46                                 + (args.length * 20));
  47                 String[] argStrings = new String[args.length];
  48                 for (int i = 0; i < args.length; ++i) {
  49                         if (args[i] == null)
  50                                 argStrings[i] = "<null>";
  51                         else
  52                                 argStrings[i] = args[i].toString();
  53                 }
  54                 int lastI = 0;
  55                 for (int i = format.indexOf('{', 0); i >= 0; i = format.indexOf('{',
  56                                 lastI)) {
  57                         if (i != 0 && format.charAt(i - 1) == '\\') {
  58                                 // It's escaped, just print and loop.
  59                                 if (i != 1)
  60                                         answer.append(format.substring(lastI, i - 1));
  61                                 answer.append('{');
  62                                 lastI = i + 1;
  63                         } else {
  64                                 // It's a format character.
  65                                 if (i > format.length() - 3) {
  66                                         // Bad format, just print and loop.
  67                                         answer.append(format.substring(lastI, format.length()));
  68                                         lastI = format.length();
  69                                 } else {
  70 //                                      int argnum = (byte) Character.digit(format.charAt(i + 1),
  71 //                                                      10);
  72                                         int argnum = (byte) (format.charAt(i + 1) - '0');
  73                                         if (argnum < 0 || format.charAt(i + 2) != '}') {
  74                                                 // Bad format, just print and loop.
  75                                                 answer.append(format.substring(lastI, i + 1));
  76                                                 lastI = i + 1;
  77                                         } else {
  78                                                 // Got a good one!
  79                                                 answer.append(format.substring(lastI, i));
  80                                                 if (argnum >= argStrings.length)
  81                                                         answer.append("<missing argument>");
  82                                                 else
  83                                                         answer.append(argStrings[argnum]);
  84                                                 lastI = i + 3;
  85                                         }
  86                                 }
  87                         }
  88                 }
  89                 if (lastI < format.length())
  90                         answer.append(format.substring(lastI, format.length()));
  91                 return answer.toString();
  92         }
  93
  94 //
  95 //      /**
  96 //       * Changes the locale of the messages.
  97 //       *
  98 //       * @param locale
  99 //       *            Locale the locale to change to.
 100 //       */
 101 //      static public ResourceBundle setLocale(final Locale locale,
 102 //                      final String resource) {
 103 //              /*
 104 //              try {
 105 //                      final ClassLoader loader = VM.bootCallerClassLoader();
 106 //                      return (ResourceBundle) AccessController
 107 //                                      .doPrivileged(new PrivilegedAction<Object>() {
 108 //                                              public Object run() {
 109 //                                                      return ResourceBundle.getBundle(resource, locale,
 110 //                                                                      loader != null ? loader : ClassLoader.getSystemClassLoader());
 111 //                                              }
 112 //                                      });
 113 //              } catch (MissingResourceException e) {
 114 //              }
 115 //              */
 116 //              /**
 117 //               * @j2sNative
 118 //               *
 119 //               * Class.forName$("java.util.ResourceBundle");
 120 //               */
 121 //              {}
 122 //              return ResourceBundle.getBundle(resource);
 123 //              //return null;
 124 //      }
 125 }