// Copyright 2010 Google Inc. All Rights Reserved.
//
// 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.api.ads.common.lib.utils;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.io.ByteSink;
import com.google.common.io.ByteSource;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
/**
* A utility class for retrieving media data.
*
* @author Adam Rogal
*/
public final class Media {
/**
* Default constructor.
*/
private Media() {}
/**
* Gets the media data {@code byte[]} located in {@code fileName}.
*
* @param fileName the media file to load
* @return the media data {@code byte[]} located in {@code fileName}
* @throws IOException if the media could not be read
*/
public static byte[] getMediaDataFromFile(String fileName) throws IOException {
return getMediaDataFromFile(new File(fileName));
}
/**
* Gets the media data {@code byte[]} located in {@code file}.
*
* @param file the media file to load
* @return the media data {@code byte[]} located in {@code file}
* @throws IOException if the media could not be read
*/
public static byte[] getMediaDataFromFile(File file) throws IOException {
return getByteArrayFromStream(new FileInputStream(file));
}
/**
* Gets the media data {@code byte[]} located at {@code url} or
* {@code null} if the media could not be loaded.
*
* @param url the media URL to load
* @return the media data {@code byte[]} located at {@code url}
* @throws IOException if the media could not be read from the URL
*/
public static byte[] getMediaDataFromUrl(String url) throws IOException {
return getMediaDataFromUrl(new URL(url));
}
/**
* Gets the media data {@code byte[]} located at {@code url} or
* {@code null} if the media could not be loaded.
*
* @param url the media URL to load
* @return the media data {@code byte[]} located at {@code url}
* @throws IOException if the media could not be read from the URL
*/
public static byte[] getMediaDataFromUrl(URL url) throws IOException {
return getByteArrayFromStream(url.openStream());
}
/**
* Gets the byte array from the input stream containing the full data from
* that stream.
*
* @param inputStream the {@code InputStream} to get the byte array from
* @return a byte array containing all data from the input stream
* @throws IOException if the stream cannot be read
*/
private static byte[] getByteArrayFromStream(final InputStream inputStream) throws IOException {
return new ByteSource() {
public InputStream openStream() {
return inputStream;
}
}.read();
}
/**
* Saves media data downloaded from an API in {@code byte[]} format into a
* file on the file system.
*
* @param mediaData the media data {@code byte[]} to store on the file system
* @param fileName the name of the file on the file system to save the media
* data into
* @throws FileNotFoundException if the file exists but is a directory, does
* not exist but cannot be created, or cannot be opened for any reason
* @throws IOException if the file cannot be written to
*/
public static void saveMediaDataToFile(byte[] mediaData, String fileName)
throws FileNotFoundException, IOException {
saveMediaDataToFile(mediaData, new File(fileName));
}
/**
* Saves media data downloaded from an API in {@code byte[]} format into a
* file on the file system.
*
* @param mediaData the media data {@code byte[]} to store on the file system
* @param file the file on the file system to save the media data into
* @throws FileNotFoundException if the file exists but is a directory, does
* not exist but cannot be created, or cannot be opened for any reason
* @throws IOException if the file cannot be written to
*/
public static void saveMediaDataToFile(byte[] mediaData, File file)
throws FileNotFoundException, IOException {
writeBytesToStream(mediaData, new FileOutputStream(file));
}
/**
* Writes the given {@code byte[]} to a stream.
*
* @throws IOException if the steam cannot be written to
*/
@VisibleForTesting
static void writeBytesToStream(byte[] bytes, final OutputStream outputStream)
throws IOException {
new ByteSink() {
public OutputStream openStream() {
return outputStream;
}
}.write(bytes);
}
}