loop functions doesn't work in the code

1) I'm trying to use for loop in some case in my code such a

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // get the file from asset Folder.
    AssetManager assetManager = getAssets();
    InputStream inputStream ;

    try {

        inputStream = assetManager.open("Data6sec.txt");    //open the file
        int size = inputStream.available();     //the size of the string

        /* Save the file & read it then close it as byte[] */
        byte[] buffer = new byte[size];
        inputStream.read(buffer);
        inputStream.close();

        String text = new String(buffer);   //convert byte to string

        **// delete the first 4 lines
        text = text.replaceAll("(?ms).*?[\r\n]+(.*)", "$1");
        text = text.replaceAll("(?ms).*?[\r\n]+(.*)", "$1");
        text = text.replaceAll("(?ms).*?[\r\n]+(.*)", "$1");
        text = text.replaceAll("(?ms).*?[\r\n]+(.*)", "$1");**

        /* View the Array list. */
        List<String> container = Arrays.asList(text.split(","));
        ArrayAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_expandable_list_item_1, container);
        ListView valList = (ListView) findViewById(R.id.lv1);
        valList.setAdapter(adapter);



    } catch (IOException e1) {
        e1.printStackTrace();
    }
}

but when i run the app on the emulator the app stops + in the command

        List<String> container = Arrays.asList(text.split(","));

text is not resolved.

why? and how i can solve this?

2) i want to read a specific elements from this array list List container = Arrays.asList(text.split(","));

how can I read it? (NOTE the list has 300 element and i want only to read every 3 elements starting from element 3)

i tried this but the app stops on the emulator:

List<String> container2 = Arrays.asList(text.split(","));
int j = 2
for(int i = 0; i <container.length; i++ ){

container2[i] = container[j];
j+=3;

}

can you help me??