jars/icu4j-4_4_2-src/main/classes/core/src/com/ibm/icu/impl/ICUData.java

   1 /*\r
   2  *******************************************************************************\r
   3  * Copyright (C) 2004-2009, International Business Machines Corporation and    *\r
   4  * others. All Rights Reserved.                                                *\r
   5  *******************************************************************************\r
   6  *\r
   7  * Created on Feb 4, 2004\r
   8  *\r
   9  */\r
  10 package com.ibm.icu.impl;\r
  11 \r
  12 import java.io.InputStream;\r
  13 import java.net.URL;\r
  14 import java.security.AccessController;\r
  15 import java.security.PrivilegedAction;\r
  16 import java.util.MissingResourceException;\r
  17 \r
  18 /**\r
  19  * Provides access to ICU data files as InputStreams.  Implements security checking.\r
  20  */\r
  21 public final class ICUData {\r
  22     /*\r
  23      * Return a URL to the ICU resource names resourceName.  The\r
  24      * resource name should either be an absolute path, or a path relative to\r
  25      * com.ibm.icu.impl (e.g., most likely it is 'data/foo').  If required\r
  26      * is true, throw an MissingResourceException instead of returning a null result.\r
  27      */\r
  28     public static boolean exists(final String resourceName) {\r
  29         URL i = null;\r
  30         if (System.getSecurityManager() != null) {\r
  31             i = AccessController.doPrivileged(new PrivilegedAction<URL>() {\r
  32                     public URL run() {\r
  33                         return ICUData.class.getResource(resourceName);\r
  34                     }\r
  35                 });\r
  36         } else {\r
  37             i = ICUData.class.getResource(resourceName);\r
  38         }\r
  39         return i != null;\r
  40     }\r
  41         \r
  42     private static InputStream getStream(final Class<?> root, final String resourceName, boolean required) {\r
  43         InputStream i = null;\r
  44         \r
  45         if (System.getSecurityManager() != null) {\r
  46             i = AccessController.doPrivileged(new PrivilegedAction<InputStream>() {\r
  47                     public InputStream run() {\r
  48                         return root.getResourceAsStream(resourceName);\r
  49                     }\r
  50                 });\r
  51         } else {\r
  52             i = root.getResourceAsStream(resourceName);\r
  53         }\r
  54 \r
  55         if (i == null && required) {\r
  56             throw new MissingResourceException("could not locate data " +resourceName, root.getPackage().getName(), resourceName);\r
  57         }\r
  58         return i;\r
  59     }\r
  60 \r
  61     private static InputStream getStream(final ClassLoader loader, final String resourceName, boolean required) {\r
  62         InputStream i = null;\r
  63         if (System.getSecurityManager() != null) {\r
  64             i = AccessController.doPrivileged(new PrivilegedAction<InputStream>() {\r
  65                     public InputStream run() {\r
  66                         return loader.getResourceAsStream(resourceName);\r
  67                     }\r
  68                 });\r
  69         } else {\r
  70             i = loader.getResourceAsStream(resourceName);\r
  71         }\r
  72         if (i == null && required) {\r
  73             throw new MissingResourceException("could not locate data", loader.toString(), resourceName);\r
  74         }\r
  75         return i;\r
  76     }\r
  77     \r
  78     public static InputStream getStream(ClassLoader loader, String resourceName){\r
  79         return getStream(loader,resourceName, false);   \r
  80     }\r
  81 \r
  82     public static InputStream getRequiredStream(ClassLoader loader, String resourceName){\r
  83         return getStream(loader, resourceName, true);\r
  84     }\r
  85 \r
  86     /*\r
  87      * Convenience override that calls getStream(ICUData.class, resourceName, false);\r
  88      */\r
  89     public static InputStream getStream(String resourceName) {\r
  90         return getStream(ICUData.class, resourceName, false);\r
  91     }\r
  92         \r
  93     /*\r
  94      * Convenience method that calls getStream(ICUData.class, resourceName, true).\r
  95      */\r
  96     public static InputStream getRequiredStream(String resourceName) {\r
  97         return getStream(ICUData.class, resourceName, true);\r
  98     }\r
  99 \r
 100     /*\r
 101      * Convenience override that calls getStream(root, resourceName, false);\r
 102      */\r
 103     public static InputStream getStream(Class<?> root, String resourceName) {\r
 104         return getStream(root, resourceName, false);\r
 105     }\r
 106     \r
 107     /*\r
 108      * Convenience method that calls getStream(root, resourceName, true).\r
 109      */\r
 110     public static InputStream getRequiredStream(Class<?> root, String resourceName) {\r
 111         return getStream(root, resourceName, true);\r
 112     }\r
 113 }\r