| 1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | package org.chromium.android_webview; |
| 6 | |
| 7 | import org.chromium.base.CalledByNative; |
| 8 | import org.chromium.base.JNINamespace; |
| 9 | |
| 10 | import android.content.res.Resources; |
| 11 | |
| 12 | import java.io.IOException; |
| 13 | import java.io.InputStream; |
| 14 | import java.io.InputStreamReader; |
| 15 | import java.lang.ref.SoftReference; |
| 16 | import java.util.HashMap; |
| 17 | import java.util.Map; |
| 18 | import java.util.NoSuchElementException; |
| 19 | import java.util.Scanner; |
| 20 | |
| 21 | @JNINamespace("android_webview::AwResource") |
| 22 | public class AwResource { |
| 23 | // The following resource ID's must be initialized by the embedder. |
| 24 | |
| 25 | // Raw resource ID for an HTML page to be displayed in the case of |
| 26 | // a specific load error. |
| 27 | public static int RAW_LOAD_ERROR; |
| 28 | |
| 29 | // Raw resource ID for an HTML page to be displayed in the case of |
| 30 | // a generic load error. (It's called NO_DOMAIN for legacy reasons). |
| 31 | public static int RAW_NO_DOMAIN; |
| 32 | |
| 33 | // String resource ID for the default text encoding to use. |
| 34 | public static int STRING_DEFAULT_TEXT_ENCODING; |
| 35 | |
| 36 | // The embedder should inject a Resources object that will be used |
| 37 | // to resolve Resource IDs into the actual resources. |
| 38 | private static Resources sResources; |
| 39 | |
| 40 | // Loading some resources is expensive, so cache the results. |
| 41 | private static Map<Integer, SoftReference<String> > sResourceCache; |
| 42 | |
| 43 | private static final int TYPE_STRING = 0; |
| 44 | private static final int TYPE_RAW = 1; |
| 45 | |
| 46 | public static void setResources(Resources resources) { |
| 47 | sResources = resources; |
| 48 | sResourceCache = new HashMap<Integer, SoftReference<String> >(); |
| 49 | } |
| 50 | |
| 51 | @CalledByNative |
| 52 | public static String getDefaultTextEncoding() { |
| 53 | return getResource(STRING_DEFAULT_TEXT_ENCODING, TYPE_STRING); |
| 54 | } |
| 55 | |
| 56 | @CalledByNative |
| 57 | public static String getNoDomainPageContent() { |
| 58 | return getResource(RAW_NO_DOMAIN, TYPE_RAW); |
| 59 | } |
| 60 | |
| 61 | @CalledByNative |
| 62 | public static String getLoadErrorPageContent() { |
| 63 | return getResource(RAW_LOAD_ERROR, TYPE_RAW); |
| 64 | } |
| 65 | |
| 66 | private static String getResource(int resid, int type) { |
| 67 | assert resid != 0; |
| 68 | assert sResources != null; |
| 69 | assert sResourceCache != null; |
| 70 | |
| 71 | String result = sResourceCache.get(resid) == null ? |
| 72 | null : sResourceCache.get(resid).get(); |
| 73 | if (result == null) { |
| 74 | switch (type) { |
| 75 | case TYPE_STRING: |
| 76 | result = sResources.getString(resid); |
| 77 | break; |
| 78 | case TYPE_RAW: |
| 79 | result = getRawFileResourceContent(resid); |
| 80 | break; |
| 81 | default: |
| 82 | throw new IllegalArgumentException("Unknown resource type"); |
| 83 | } |
| 84 | |
| 85 | sResourceCache.put(resid, new SoftReference<String>(result)); |
| 86 | } |
| 87 | return result; |
| 88 | } |
| 89 | |
| 90 | private static String getRawFileResourceContent(int resid) { |
| 91 | assert resid != 0; |
| 92 | assert sResources != null; |
| 93 | |
| 94 | InputStreamReader isr = null; |
| 95 | String result = null; |
| 96 | |
| 97 | try { |
| 98 | isr = new InputStreamReader( |
| 99 | sResources.openRawResource(resid)); |
| 100 | // \A tells the scanner to use the beginning of the input |
| 101 | // as the delimiter, hence causes it to read the entire text. |
| 102 | result = new Scanner(isr).useDelimiter("\\A").next(); |
| 103 | } catch (Resources.NotFoundException e) { |
| 104 | return ""; |
| 105 | } catch (NoSuchElementException e) { |
| 106 | return ""; |
| 107 | } |
| 108 | finally { |
| 109 | try { |
| 110 | if (isr != null) { |
| 111 | isr.close(); |
| 112 | } |
| 113 | } catch(IOException e) { |
| 114 | } |
| 115 | } |
| 116 | return result; |
| 117 | } |
| 118 | } |