Save best point

Here is my code: import greenfoot.*; import java.io.*; import java.lang.*; import java.util.*; public class BestScore extends Actor { private Formatter x; private Scanner y; private int best; int number; public BestScore(int number) { this.number = number; } public void OpenFile(){ try { x = new Formatter("record.txt"); y = new Scanner (new File("record.txt") ); } catch (Exception e){ System.out.println("You have an error!"); } } public void addRecords(){ if (number>best) { x.format("%s", number); } } public void closeFile(){ x.close(); } public void readFile() { String s="0"; while(y.hasNext() ) { s = y.next(); } best = Integer.parseInt(s); } }

Well: new File("record.txt") opens a file which must exist in the "current" directory. That could be pretty much any directory if you have exported your application, though it depends on how you run it. Where is the record.txt file? Does it exist in the same directory as the .jar file? How are you running the jar file?

It exists in the same directory as jar file. How I run the jar file: right click on the file, then open with Java(TM) Platform SE binary

Ok: how do you know that the problem is that it can't find the file? From the code snippet you've posted, there's no obvious error message output except to System.out which you won't see if you run the jar via the GUI.

I'm not sure that it can't find the file, but I think so, because by in record.txt best point = 120, and in my program best point = 0. And however it appears 0 on the screen : public void readFile() { String s="0"; while(y.hasNext() ) { s = y.next(); } best = Integer.parseInt(s); } And when I run it in Greenfoot, it gets best point from the record.txt and converts it to int (that's what I want) , but when I run jar file, it doesn't work normally(. Maybe I should post the source code?

From the sounds of it, the problem is really that the current directory isn't reliably set to anything in particular when you run the jar file. You could try hard-coding the full path to the file, or prompt the user for the file location.

You might like to look at this: http://www.bluej.org/help/archive.html#tip10

Thank you! Now I can read the file, but I don't know to write in it. And why I can't write: public InputStream openFile(String fileName) throws IOException { URL url = getClass().getClassLoader().getResource(fileName); if(url == null) throw new IOException("File not found: " + fileName); return url.toString(); } FileInputStream in = new FileInputStream(openFile("record.txt")); ?

I think that the instructions at http://www.bluej.org/help/archive.html#tip10 aren't actually helping you here - the technique described there can help you read from a file which has been included inside your jar, but you won't be able to write to it. Your problem is a bit different: you want to be able to read and write to a file which sits in the same place as the jar file. Did you try hard-coding the full path to the file, as I suggested earlier?

Yes, I did, look: x = new Formatter("D:\\Program Files\\Greenfoot\\scenarios\\appleGame.jar\\record.txt"); y = new Scanner(new File("D:\\Program Files\\Greenfoot\\scenarios\\appleGame.jar\\record.txt")); but it didn't help ( (In Greenfoot it runs normally, but the path is a bit different x = new Formatter("D:\\Program Files\\Greenfoot\\scenarios\\appleGame\\record.txt"); ) Maybe the system can not open jar file??

Ok, I'm a bit confused now. Is the record.txt file you want to open in the same *directory* as the jar file, like you said earlier, or is it actually *inside* the jar file? If the former, then the path you specified looks wrong; it should probably be "D:\\Program Files\\Greenfoot\\scenarios\\record.txt". If the latter, you can use the technique given by mik to read the file, but you cannot write to the file. There is no simple way to write to a file which is inside a jar file. And, you cannot open a file inside a jar file in the same way you can open other files; the operating system doesn't treat them the same way.

Actually davmac, I challenge what you said earlier in the discussion. You said that the new File("BestPoint.txt"); command opens up a file if only it exsists. However, in my Head First Java book, it said that It opens the file if created, however, if it's not created, it creates a new file. However, it will be empty, so var "b" will be considered null if you do this command: String b = new BufferedReader(new FileReader(new File("TheFileNeverCreated.txt"))).readLine();