1 /*
   2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.util.resources;
  27 
  28 import java.io.InputStream;
  29 import java.security.AccessController;
  30 import java.security.PrivilegedActionException;
  31 import java.security.PrivilegedExceptionAction;
  32 import java.util.Collections;
  33 import java.util.Enumeration;
  34 import java.util.ResourceBundle;
  35 import java.util.Set;
  36 
  37 /**
  38  * BreakIteratorResourceBundle is an abstract class for loading BreakIterator
  39  * data (rules or dictionary) from each module. An implementation class must
  40  * implement getBreakIteratorInfo() that returns an instance of the
  41  * corresponding BreakIteratorInfo (basename).  The data name is taken from the
  42  * BreakIteratorInfo instance.
  43  *
  44  * <p>For example, if the given key is "WordDictionary" and Locale is "th", the
  45  * data name is taken from a BreakIteratorInfo_th and the key's value is
  46  * "thai_dict".  Its data thai_dict is loaded from the Module of the
  47  * implementation class of this class.
  48  */
  49 
  50 public abstract class BreakIteratorResourceBundle extends ResourceBundle {
  51     // If any keys that are not for data names are added to BreakIteratorInfo*,
  52     // those keys must be added to NON_DATA_KEYS.
  53     private static final Set<String> NON_DATA_KEYS = Set.of("BreakIteratorClasses");
  54 
  55     private volatile Set<String> keys;
  56 
  57     /**
  58      * Returns an instance of the corresponding {@code BreakIteratorInfo} (basename).
  59      * The instance shouldn't have its parent.
  60      */
  61     protected abstract ResourceBundle getBreakIteratorInfo();
  62 
  63     @Override
  64     protected Object handleGetObject(String key) {
  65         if (NON_DATA_KEYS.contains(key)) {
  66             return null;
  67         }
  68         ResourceBundle info = getBreakIteratorInfo();
  69         if (!info.containsKey(key)) {
  70             return null;
  71         }
  72         String path = getClass().getPackage().getName().replace('.', '/')
  73                       + '/' + info.getString(key);
  74         byte[] data;
  75         try (InputStream is = getResourceAsStream(path)) {
  76             data = is.readAllBytes();
  77         } catch (Exception e) {
  78             throw new InternalError("Can't load " + path, e);
  79         }
  80         return data;
  81     }
  82 
  83     private InputStream getResourceAsStream(String path) throws Exception {
  84         PrivilegedExceptionAction<InputStream> pa;
  85         pa = () -> getClass().getModule().getResourceAsStream(path);
  86         InputStream is;
  87         try {
  88             is = AccessController.doPrivileged(pa);
  89         } catch (PrivilegedActionException e) {
  90             throw e.getException();
  91         }
  92         return is;
  93     }
  94 
  95     @Override
  96     public Enumeration<String> getKeys() {
  97         return Collections.enumeration(keySet());
  98     }
  99 
 100     @Override
 101     protected Set<String> handleKeySet() {
 102         if (keys == null) {
 103             ResourceBundle info = getBreakIteratorInfo();
 104             Set<String> k = info.keySet();
 105             k.removeAll(NON_DATA_KEYS);
 106             synchronized (this) {
 107                 if (keys == null) {
 108                     keys = k;
 109                 }
 110             }
 111         }
 112         return keys;
 113     }
 114 }