private void copyBigDataToSD(String strOutFileName) throws IOException
{
    File fData = http://www.mamicode.com/new File(strOutFileName);
    try{
        if (!fData.exists()){   //not exist, copy
            InputStream myInput;
            OutputStream myOutput = new FileOutputStream(strOutFileName);
            myInput = this.getAssets().open("data.bin");
            byte[] buffer = new byte[1024];
            int length = myInput.read(buffer);
            while(length > 0)
            {
                myOutput.write(buffer, 0, length);
                length = myInput.read(buffer);
            }

            myOutput.flush();
            myInput.close();
            myOutput.close();
        }
    }catch (Exception e ){
        Log.e(TAG, "file data.bin ERROR!");
    }
}

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