Google Cloud StorageのJava APIの概要についての
ドキュメントを翻訳しています。
翻訳元は
こちらです。
このドキュメントは、Google App Engineアプリケーションから
Google Cloud Storageの機能を呼び出す方法について
説明しています。
現在は試験的運用中なので、今後変更があるかもしれません。
第1回は
こちら、第2回は
こちら、第3回は
こちら、
第4回は
こちら、第5回は
こちら、第6回は
こちら、
第7回は
こちら、第８回は
こちら、第9回は
こちら、
第10回は
こちら、第11回は
こちらです。
- 以下のコードでGuestbookServlet.javaのdoGet()メソッドを上書きして、BACKETNAMEとFILENAMEをあなたのバケット及びファイル名に書き換えます。
/**
* Copyright 2011 Google Inc. All Rights Reserved.
* Create, Write, Read, and Finalize Cloud Storage objects.
* Access your app at: http://myapp.appspot.com/
**/
@SuppressWarnings("serial")
/**
* Copyright 2011 Google Inc. All Rights Reserved.
* Create, Write, Read, and Finalize Cloud Storage objects.
* Access your app at: http://myapp.appspot.com/
**/
@SuppressWarnings("serial")
public class GuestbookServlet extends HttpServlet {
public static final String BUCKETNAME = "YOUR_BUCKET_NAME";
public static final String FILENAME = "YOUR_FILE_NAME";
@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
resp.setContentType("text/plain");
resp.getWriter().println("Hello, world from java");
FileService fileService = FileServiceFactory.getFileService();
GSFileOptionsBuilder optionsBuilder = new GSFileOptionsBuilder()
.setBucket(BUCKETNAME)
.setKey(FILENAME)
.setMimeType("text/html")
.setAcl("public_read")
.addUserMetadata("myfield1", "my field value");
AppEngineFile writableFile =
fileService.createNewGSFile(optionsBuilder.build());
// Open a channel to write to it
boolean lock = false;
FileWriteChannel writeChannel =
fileService.openWriteChannel(writableFile, lock);
// Different standard Java ways of writing to the channel
// are possible. Here we use a PrintWriter:
PrintWriter out = new PrintWriter(Channels.newWriter(writeChannel, "UTF8"));
out.println("The woods are lovely dark and deep.");
out.println("But I have promises to keep.");
// Close without finalizing and save the file path for writing later
out.close();
String path = writableFile.getFullPath();
// Write more to the file in a separate request:
writableFile = new AppEngineFile(path);
// Lock the file because we intend to finalize it and
// no one else should be able to edit it
lock = true;
writeChannel = fileService.openWriteChannel(writableFile, lock);
// This time we write to the channel directly
writeChannel.write(ByteBuffer.wrap
("And miles to go before I sleep.".getBytes()));
// Now finalize
writeChannel.closeFinally();
resp.getWriter().println("Done writing...");
// At this point, the file is visible in App Engine as:
// "/gs/BUCKETNAME/FILENAME"
// and to anybody on the Internet through Cloud Storage as:
// (http://storage.googleapis.com/BUCKETNAME/FILENAME)
// We can now read the file through the API:
String filename = "/gs/" + BUCKETNAME + "/" + FILENAME;
AppEngineFile readableFile = new AppEngineFile(filename);
FileReadChannel readChannel =
fileService.openReadChannel(readableFile, false);
// Again, different standard Java ways of reading from the channel.
BufferedReader reader =
new BufferedReader(Channels.newReader(readChannel, "UTF8"));
String line = reader.readLine();
resp.getWriter().println("READ:" + line);
// line = "The woods are lovely, dark, and deep."
readChannel.close();
}
}
インストール不要･無料のKaede翻訳ツール:
http://kaedetrans-hrd.appspot.com/
