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POUpload an image to google app engine blobstore with java programmatically
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copied!<p>I have already watched "Writing Files to the Blobstore (Experimental)" in the google app engine page.</p> <p>This is what I have :</p> <pre><code>// Get a file service FileService fileService = FileServiceFactory.getFileService(); // Create a new Blob file with mime-type "text/plain" AppEngineFile file = fileService.createNewBlobFile("text/plain"); // Open a channel to write to it boolean lock = false; FileWriteChannel writeChannel = fileService.openWriteChannel(file, 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 = file.getFullPath(); // Write more to the file in a separate request: file = new AppEngineFile(path); // This time lock because we intend to finalize lock = true; writeChannel = fileService.openWriteChannel(file, 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(); // Later, read from the file using the file API lock = false; // Let other people read at the same time FileReadChannel readChannel = fileService.openReadChannel(file, false); // Again, different standard Java ways of reading from the channel. BufferedReader reader = new BufferedReader(Channels.newReader(readChannel, "UTF8")); String line = reader.readLine(); // line = "The woods are lovely dark and deep." readChannel.close(); // Now read from the file using the Blobstore API BlobKey blobKey = fileService.getBlobKey(file); BlobstoreService blobStoreService = BlobstoreServiceFactory.getBlobstoreService(); String segment = new String(blobStoreService.fetchData(blobKey, 30, 40)); </code></pre> <p>Unfortunately, this is just for text file. I would assume that <code>PrintWriter</code> should be changed to <code>ImageWriter</code> but in google app engine, <code>ImageWriter</code> is not supported. What should I do?</p>

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