I know this is probably possible using Streams, but I wasn't sure the correct syntax.

I would like to pass a string to the Save method and have it gzip the string and upload it to Amazon S3 without ever being written to disk. The current method inefficiently reads/writes to disk in between.

The S3 PutObjectRequest has a constructor with InputStream input as an option.

import java.io.*;
import java.util.zip.GZIPOutputStream;

import com.amazonaws.auth.PropertiesCredentials;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3Client;
import com.amazonaws.services.s3.model.PutObjectRequest;

public class FileStore {

    public static void Save(String data) throws IOException
    {
        File file = File.createTempFile("filemaster-", ".htm");
        file.deleteOnExit();

        Writer writer = new OutputStreamWriter(new FileOutputStream(file));
        writer.write(data);
        writer.flush();
        writer.close();

        String zippedFilename = gzipFile(file.getAbsolutePath());
        File zippedFile = new File(zippedFilename);
        zippedFile.deleteOnExit();

        AmazonS3 s3 = new AmazonS3Client(new PropertiesCredentials(
                new FileInputStream("AwsCredentials.properties")));

        String bucketName = "mybucket";
        String key = "test/" + zippedFile.getName();

        s3.putObject(new PutObjectRequest(bucketName, key, zippedFile));

    }

    public static String gzipFile(String filename) throws IOException
    {
        try {
            // Create the GZIP output stream
            String outFilename = filename + ".gz";
            GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(outFilename));

            // Open the input file
            FileInputStream in = new FileInputStream(filename);

            // Transfer bytes from the input file to the GZIP output stream
            byte[] buf = new byte[1024];
            int len;
            while ((len = in.read(buf)) > 0) {
                out.write(buf, 0, len);
            }
            in.close();

            // Complete the GZIP file
            out.finish();
            out.close();

            return outFilename;
        } catch (IOException e) {
            throw e;
        }
    }


}