A quick code example today: serializing a Java object to Google Cloud storage. write_object stands for the object being written. This code depends on the App Engine libraries for Java, and the Google Cloud Storage libraries.
GcsService gcs_service = GcsServiceFactory.createGcsService();
GcsFilename gcs_filename = new GcsFilename(AppIdentityServiceFactory.getAppIdentityService().getDefaultGcsBucketName(), "subfolder_within_bucket" + "/" + "filename.extension");
GcsFileOptions gcs_options = GcsFileOptions.getDefaultInstance();
GcsOutputChannel output = gcs_service.createOrReplace(gcs_filename, gcs_options);
ObjectOutputStream oos = new ObjectOutputStream(Channels.newOutputStream(output));
oos.writeObject(write_object);
oos.flush();
oos.close();
output.close();