Re-add RTMP extension classes

extensions/rtmp/src/main/AndroidManifest.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- 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.
+-->
+
+<manifest package="com.google.android.exoplayer2.ext.rtmp"/>

extensions/rtmp/src/main/java/com/google/android/exoplayer2/ext/rtmp/RtmpDataSource.java

+/*
+ * 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.ext.rtmp;
+
+import android.net.Uri;
+import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DataSpec;
+import com.google.android.exoplayer2.upstream.TransferListener;
+import java.io.IOException;
+import net.butterflytv.rtmp_client.RtmpClient;
+import net.butterflytv.rtmp_client.RtmpClient.RtmpIOException;
+
+/**
+ * A Real-Time Messaging Protocol (RTMP) {@link DataSource}.
+ */
+public final class RtmpDataSource implements DataSource {
+
+  @Nullable private final TransferListener<? super RtmpDataSource> listener;
+
+  private RtmpClient rtmpClient;
+  private Uri uri;
+
+  public RtmpDataSource() {
+    this(null);
+  }
+
+  /**
+   * @param listener An optional listener.
+   */
+  public RtmpDataSource(@Nullable TransferListener<? super RtmpDataSource> listener) {
+    this.listener = listener;
+  }
+
+  @Override
+  public long open(DataSpec dataSpec) throws RtmpIOException {
+    rtmpClient = new RtmpClient();
+    rtmpClient.open(dataSpec.uri.toString(), false);
+
+    this.uri = dataSpec.uri;
+    if (listener != null) {
+      listener.onTransferStart(this, dataSpec);
+    }
+    return C.LENGTH_UNSET;
+  }
+
+  @Override
+  public int read(byte[] buffer, int offset, int readLength) throws IOException {
+    int bytesRead = rtmpClient.read(buffer, offset, readLength);
+    if (bytesRead == -1) {
+      return C.RESULT_END_OF_INPUT;
+    }
+    if (listener != null) {
+      listener.onBytesTransferred(this, bytesRead);
+    }
+    return bytesRead;
+  }
+
+  @Override
+  public void close() {
+    if (uri != null) {
+      uri = null;
+      if (listener != null) {
+        listener.onTransferEnd(this);
+      }
+    }
+    if (rtmpClient != null) {
+      rtmpClient.close();
+      rtmpClient = null;
+    }
+  }
+
+  @Override
+  public Uri getUri() {
+    return uri;
+  }
+
+}

extensions/rtmp/src/main/java/com/google/android/exoplayer2/ext/rtmp/RtmpDataSourceFactory.java

+/*
+ * 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.ext.rtmp;
+
+import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.HttpDataSource.Factory;
+import com.google.android.exoplayer2.upstream.TransferListener;
+
+/**
+ * A {@link Factory} that produces {@link RtmpDataSource}.
+ */
+public final class RtmpDataSourceFactory implements DataSource.Factory {
+
+  @Nullable
+  private final TransferListener<? super RtmpDataSource> listener;
+
+  public RtmpDataSourceFactory() {
+    this(null);
+  }
+
+  /**
+   * @param listener An optional listener.
+   */
+  public RtmpDataSourceFactory(@Nullable TransferListener<? super RtmpDataSource> listener) {
+    this.listener = listener;
+  }
+
+  @Override
+  public DataSource createDataSource() {
+    return new RtmpDataSource(listener);
+  }
+
+}