Java , get specific String from File

Question

I want to get a specific String from a Text file.

E.g i only want to have the indicated part (3rd Line) to be saved in new File

19:22:08.999 T:5804  NOTICE: Aero is enabled
19:22:08.999 T:5804  NOTICE: special://xbmc/ is mapped to: C:\Program Files (x86)\Kodi
19:22:08.999 T:5804  NOTICE: key://xbmcbin/ is mapped to: C:\Program Files (x86)\Kodi
     I want this part -----> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
19:22:08.999 T:5804  NOTICE: special://xbmcbinaddons/ is mapped to: C:\Program Files (x86)\Kodi/addons

My code:

public static void main(String[] args) throws IOException {
    ArrayList<String> result = new ArrayList<>();
    Scanner s = null; 
    try { 

        s = new Scanner(new BufferedReader(new FileReader("C:/test.txt"))); 

        while (s.hasNextLine()) {
            result.add(s.nextLine());
        }
    } finally {
        if (s != null){
            s.close();
        }
    } System.out.println(result);
} 

I have everything saved in a ArrayList but how can i now

1. Save only one element of this ArrayList
2. Save only part of a line (the bold one) in a variable or a new file.

   ---

EDIT I solved everything Thank you very much for your help espacially @dustytrash

Answer 1

You check each line to see if it contains the value you need. When you find the value you can stop scanning (Assuming you're only looking for 1 line). Then you can parse the line if needed.

The following produced 'key://xbmcbin/ is mapped to: C:\Program Files (x86)\Kodi' as per your example:

public static void main(String[] args) throws IOException 
{
    String result = "";
    Scanner s = null; 
    try 
    {
        final String searchKey = "key:";
        final String trimFromLine = "Kodi";
        s = new Scanner(new BufferedReader(new FileReader("test.txt"))); 

        while (s.hasNextLine() && result.isEmpty()) 
        {
            String nextLine = s.nextLine();
            if (nextLine.contains(searchKey))
            {
                // Trim everything from the end, to the beginning character of our searchKey (in this case 'key:')
                result = nextLine.substring(nextLine.indexOf(searchKey));

                // Take everything from the beginning to the end of the beginning character in our trimFromLine (in the case start index of 'Kodi')
                result = result.substring(0, result.indexOf(trimFromLine));
            }
        }
    } 
    finally 
    {
        if (s != null)
        {
            s.close();
        }
    } System.out.println(result);
}