1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.graphics.fonts;
18 
19 import com.android.layoutlib.bridge.impl.DelegateManager;
20 import com.android.tools.layoutlib.annotations.LayoutlibDelegate;
21 
22 import android.annotation.NonNull;
23 import android.content.res.AssetManager;
24 
25 import java.io.IOException;
26 import java.io.InputStream;
27 import java.nio.ByteBuffer;
28 import java.nio.ByteOrder;
29 import java.nio.channels.Channels;
30 import java.nio.channels.ReadableByteChannel;
31 
32 /**
33  * Delegate implementing the native methods of android.graphics.fonts.Font$Builder
34  * <p>
35  * Through the layoutlib_create tool, the original native methods of Font$Builder have been
36  * replaced by calls to methods of the same name in this delegate class.
37  * <p>
38  * This class behaves like the original native implementation, but in Java, keeping previously
39  * native data into its own objects and mapping them to int that are sent back and forth between it
40  * and the original Font$Builder class.
41  *
42  * @see DelegateManager
43  */
44 public class Font_Builder_Delegate {
45 
46     @LayoutlibDelegate
createBuffer(@onNull AssetManager am, @NonNull String path, boolean isAsset, int cookie)47     /*package*/ static ByteBuffer createBuffer(@NonNull AssetManager am, @NonNull String path,
48             boolean isAsset, int cookie) throws IOException {
49 
50         if (path.isBlank()) {
51             return null;
52         }
53 
54         try (InputStream assetStream = isAsset ? am.open(path, AssetManager.ACCESS_BUFFER)
55                 : am.openNonAsset(cookie, path, AssetManager.ACCESS_BUFFER)) {
56 
57             int capacity = assetStream.available();
58             ByteBuffer buffer = ByteBuffer.allocateDirect(capacity);
59             buffer.order(ByteOrder.nativeOrder());
60             ReadableByteChannel channel = Channels.newChannel(assetStream);
61             channel.read(buffer);
62 
63             if (assetStream.read() != -1) {
64                 throw new IOException("Unable to access full contents of " + path);
65             }
66 
67             return buffer;
68         }
69     }
70 }
71