| /* |
| * Copyright 2022 Google LLC |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.google.android.libraries.mobiledatadownload.file.transforms; |
| |
| import android.net.Uri; |
| import com.google.android.libraries.mobiledatadownload.file.common.Fragment; |
| import com.google.android.libraries.mobiledatadownload.file.spi.Transform; |
| import java.io.BufferedOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| /** |
| * BufferTransform takes writes and holds on to it until enough has been written to justify flushing |
| * to the disk. Reads are not affected by this transform. |
| * |
| * <p>A flush of the buffer can be performed using {@link OutputStream#flush()}. |
| * |
| * <p>It is configured using transform fragment int param {@code size}. For example: {@code |
| * file:///tmp/file#transform=buffer(size=1024)}. |
| */ |
| public class BufferTransform implements Transform { |
| |
| private static final int DEFAULT_BUFFER_SIZE = 8192; |
| |
| private static final String TRANSFORM_NAME = "buffer"; |
| private static final String SUBPARAM_SIZE = "size"; |
| |
| @Override |
| public String name() { |
| return TRANSFORM_NAME; |
| } |
| |
| @Override |
| public InputStream wrapForRead(Uri uri, InputStream wrapped) throws IOException { |
| return wrapped; |
| } |
| |
| @Override |
| public OutputStream wrapForAppend(Uri uri, OutputStream wrapped) throws IOException { |
| return wrapForWrite(uri, wrapped); |
| } |
| |
| @Override |
| public OutputStream wrapForWrite(Uri uri, OutputStream wrapped) throws IOException { |
| String bufferSizeStr = Fragment.getTransformSubParam(uri, name(), SUBPARAM_SIZE); |
| int bufferSize = DEFAULT_BUFFER_SIZE; |
| if (bufferSizeStr != null) { |
| bufferSize = Integer.parseInt(bufferSizeStr); |
| } |
| return new BufferedOutputStream(wrapped, bufferSize); |
| } |
| } |