| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * 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.exoplayer2.metadata.emsg; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| |
| /** |
| * Encodes data that can be decoded by {@link EventMessageDecoder}. This class isn't thread safe. |
| */ |
| public final class EventMessageEncoder { |
| |
| private final ByteArrayOutputStream byteArrayOutputStream; |
| private final DataOutputStream dataOutputStream; |
| |
| public EventMessageEncoder() { |
| byteArrayOutputStream = new ByteArrayOutputStream(512); |
| dataOutputStream = new DataOutputStream(byteArrayOutputStream); |
| } |
| |
| /** |
| * Encodes an {@link EventMessage} to a byte array that can be decoded by {@link |
| * EventMessageDecoder}. |
| * |
| * @param eventMessage The event message to be encoded. |
| * @return The serialized byte array. |
| */ |
| public byte[] encode(EventMessage eventMessage) { |
| byteArrayOutputStream.reset(); |
| try { |
| writeNullTerminatedString(dataOutputStream, eventMessage.schemeIdUri); |
| String nonNullValue = eventMessage.value != null ? eventMessage.value : ""; |
| writeNullTerminatedString(dataOutputStream, nonNullValue); |
| dataOutputStream.writeLong(eventMessage.durationMs); |
| dataOutputStream.writeLong(eventMessage.id); |
| dataOutputStream.write(eventMessage.messageData); |
| dataOutputStream.flush(); |
| return byteArrayOutputStream.toByteArray(); |
| } catch (IOException e) { |
| // Should never happen. |
| throw new RuntimeException(e); |
| } |
| } |
| |
| private static void writeNullTerminatedString(DataOutputStream dataOutputStream, String value) |
| throws IOException { |
| dataOutputStream.writeBytes(value); |
| dataOutputStream.writeByte(0); |
| } |
| } |