Android RandomAccessFile usage from resource

Question

How can I access an Android resource using RandomAccessFile in Java?

Here is how I would like this to work (but it doesn't):

String fileIn = resources.getResourceName(resourceID);
Log.e("fileIn", fileIn);
//BufferedReader buffer = new BufferedReader(new InputStreamReader(fileIn));

RandomAccessFile buffer = null;
try {
  buffer = new RandomAccessFile(fileIn, "r");
} catch (FileNotFoundException e) {
  Log.e("err", ""+e);
}

Log output:

fileIn(6062): ls3d.gold.paper:raw/wwe_obj

The following exception appears in my console:

11-26 15:06:35.027: ERROR/err(6062): java.io.FileNotFoundException: /ls3d.gold.paper:raw/wwe_obj (No such file or directory)

Answer 1

Like you, my situation is much easier if I can use an instance of RandomAccessFile. The solution I finally arrived at is to simply copy the resource into a file in cache, then open that file with RandomAccessFile:

/**
 * Copies raw resource to a cache file.
 * @return File reference to cache file.
 * @throws IOException
 */
private File createCacheFile(Context context, int resourceId, String filename)
    throws IOException {
  File cacheFile = new File(context.getCacheDir(), filename);

  if (cacheFile.createNewFile() == false) {
    cacheFile.delete();
    cacheFile.createNewFile();
  }

  // from: InputStream to: FileOutputStream.
  InputStream inputStream = context.getResources().openRawResource(resourceId);
  FileOutputStream fileOutputStream = new FileOutputStream(cacheFile);
  int count;
  byte[] buffer = new byte[1024 * 512];
  while ((count = inputStream.read(buffer)) != -1) {
    fileOutputStream.write(buffer, 0, count);
  }

  fileOutputStream.close();
  inputStream.close();

  return cacheFile;
}

You would use this method thusly:

File cacheFile = createCacheFile(context, resourceId, "delete-me-please");
RandomAccessFile randomAccessFile = new RandomAccessFile(cacheFile, "r");

// Insert useful things that people want.

randomAccessFile.close();
cacheFile.delete();