Q: How to get access to raw resources that I put in res folder? In J2ME, I've do this like that: 
getClass().getResourceAsStream("/raw_resources.dat");
But in android, I always get null on this, why?

A: Android access to raw resources
An advance approach is using Kotlin Extension function
fun Context.getRawInput(@RawRes resourceId: Int): InputStream {
    return resources.openRawResource(resourceId)
}

One more interesting thing is extension function use that is defined in Closeable scope
For example you can work with input stream in elegant way without handling Exceptions and memory managing
fun Context.readRaw(@RawRes resourceId: Int): String {
    return resources.openRawResource(resourceId).bufferedReader(Charsets.UTF_8).use { it.readText() }
}


A: TextView txtvw = (TextView)findViewById(R.id.TextView01);
        txtvw.setText(readTxt());

 private String readTxt()
    {
    InputStream raw = getResources().openRawResource(R.raw.hello);

    ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();

    int i;
    try
    {
        i = raw.read();
        while (i != -1)
        {
            byteArrayOutputStream.write(i);
            i = raw.read();
        }
        raw.close();
    }
    catch (IOException e)
    {
        // TODO Auto-generated catch block

        e.printStackTrace();
    }


    return byteArrayOutputStream.toString();

}

TextView01:: txtview in linearlayout
hello:: .txt file in res/raw folder   (u can access ny othr folder as wel)
Ist 2 lines are 2 written in onCreate() method
rest is to be written in class extending Activity!!

A: getClass().getResourcesAsStream() works fine on Android. Just make sure the file you are trying to open is correctly embedded in your APK (open the APK as ZIP).
Normally on Android you put such files in the assets directory. So if you put the raw_resources.dat in the assets subdirectory of your project, it will end up in the assets directory in the APK and you can use:
getClass().getResourcesAsStream("/assets/raw_resources.dat");

It is also possible to customize the build process so that the file doesn't land in the assets directory in the APK.

A: 
InputStream in = getResources().openRawResource(resourceName);

This will work correctly. Before that you have to create the xml file / text file in raw resource. Then it will be accessible.
Edit   Some times com.andriod.R will be imported if there is any error in layout file or image names. So You have to import package correctly,  then only the raw file will be accessible.

A: InputStream raw = context.getAssets().open("filename.ext");

Reader is = new BufferedReader(new InputStreamReader(raw, "UTF8"));


A: In some situations we have to get image from drawable or raw folder using image name instead if generated id 
// Image View Object 
        mIv = (ImageView) findViewById(R.id.xidIma);
// create context Object for  to Fetch  image from resourse 
Context mContext=getApplicationContext();

// getResources().getIdentifier("image_name","res_folder_name", package_name);

// find out below example 
    int i = mContext.getResources().getIdentifier("ic_launcher","raw", mContext.getPackageName());

// now we will get contsant id for that image       
        mIv.setBackgroundResource(i);


A: For raw files, you should consider creating a raw folder inside res directory and then call getResources().openRawResource(resourceName) from your activity.

A: This worked for for me: getResources().openRawResource(R.raw.certificate)
