jars/icu4j-4_8_1_1/main/classes/core/src/com/ibm/icu/impl/ICUData.java

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