Reading an int from a particular location in a file

Question

Hi, I've seen other topics about reading ints from files/strings etc, but I don't think I've found one the same as this.
I have an input file "maxSolution.sol" that contains an int that I need to use in my program
c Parsing PB file...
c Converting 0 PB-constraints to clauses...
c -- Unit propagations: (none)
c -- Detecting intervals from adjacent constraints: (none)
c -- Clauses(.)/Splits(s): (none)
c ==================================[MINISAT+]==================================
c | Conflicts | Original | Learnt | Progress |
c | | Clauses Literals | Max Clauses Literals LPC | |
c ==============================================================================
c | 0 | 0 0 | 0 0 0 nan | 0.000 % |
c ==============================================================================
c Found solution: -1
c Optimal solution: -1
s OPTIMUM FOUND
v x0001 -x0101 -x0200 -x0201 -x0800
c _______________________________________________________________________________
c
c restarts : 1
c conflicts : 0 (nan /sec)
c decisions : 2 (inf /sec)
c propagations : 0 (nan /sec)
c inspects : 0 (nan /sec)
c CPU time : 0 s
c _______________________________________________________________________________
The int that I require is the one that appears after "Optimal Solution: ". I actually require the absolute value of this, so I have tried the following
public int maxInputReader(String s) throws IOException
String optimal = "Optimal Solution:";
int mines = 0;
File input = new File(s);
Scanner filein = new Scanner(input);
while(filein.hasNext())
if(filein.next() == optimal)
mines = Math.abs(Integer.parseInt(filein.next()));
return mines;
However, when I run this method, it returns 0, the initial value for the int mines, could anyone give me a hand as to what I am doing wrong?

Answer 1

much better:
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class RegExpTest {
     public RegExpTest(){
          try {
             // Create matcher on file
             Pattern pattern = Pattern.compile("Optimal solution:\\s*(\\-)\\d");
             Matcher matcher = pattern.matcher(fromFile("your_file_path_here.txt"));
             // Find all matches
             while (matcher.find()) {
                 // Get the matching string
                 String match = matcher.group();
                 System.out.println("Line : "+match);
                 int i = Integer.parseInt(match.substring(match.indexOf(':')+1).trim());
                 System.out.println("Number: "+i);
         } catch (IOException e) {
              e.printStackTrace();
     //Converts the contents of a file into a CharSequence
    // suitable for use by the regex package.
    public CharSequence fromFile(String filename) throws IOException {
        FileInputStream fis = new FileInputStream(filename);
        FileChannel fc = fis.getChannel();
        // Create a read-only CharBuffer on the file
        ByteBuffer bbuf = fc.map(FileChannel.MapMode.READ_ONLY, 0, (int)fc.size());
        CharBuffer cbuf = Charset.forName("8859_1").newDecoder().decode(bbuf);
        return cbuf;
    public static void main(String[] args) {
          new RegExpTest();
}