Reading and writing files in Mac OS X

Hello, I am "kind of" experienced with Java (read a few books, and took one course in highschool, and I fool around with it from time to time).
All of this however was on Windows XP, and all from the command line. Because I now have a Macbook Pro, I wish to start programming java on Mac OSX naturally. I've gotten over the shock and awe of using Xcode (I had never use a "package" before with multiple components), but I have come across a problem. I referenced one of my Java books on how to read from a .txt file (my intended program needs a database), but I've been trying for a few hours now, and I just can't seem to get it to work at all.
I want to read the entire file and save it as a String. I don't know if there is a different procedure on OSX than Windows, but here is what I am using:
import java.io.*;etc. etc.
public String readPlease() {
     String str = "";
     try {
          FileReader file = new FileReader("database.txt");
          BufferedReader buff = new BufferedReader(file);
          str = buff.readLine();
          buff.close();
          return str;
     } catch (IOException e) {
          return e.toString();
}And it is returning:
java.io.FileNotFoundException: database.txt (No such file or directory)The .java file and the .txt file are in the same folder (src) and I've tried it while its in "resources" and "bin" (where the .class files are).

That file needs to be in the directory that you launch your program from.
Is that where it is? It might help if you showed us the command you are using to execute and where you are relative to your file etc.
Also this
BufferedReader buff = new BufferedReader(file);
str = buff.readLine();
buff.close();is going to only read one line of the file. Do you know that?
If you want to read multiple lines you'll need a loop, and you should be using a StringBuilder and appending to it to build your String. Then you can call toString on the StringBuilder instance once at the end to get your string.

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