Sample simple File IO

FileLoader.java

package com.n1nja.fileio;
import java.io.*;
public class FileLoader {
	public static void main(String[] args) {
		new FileLoader(args);
	}
	//The file to read
	private final File f = new File("rpsls.rps");
	private BufferedReader in;
	private FileLoader(String...r) {
		//Try the contained code. If it throws an exception, break. This is 
		//just standard Java exception handling.
		try {
			//Build a new reader around the file. It requires two levels because
			//the BufferedReader provides handy convienience methods like 
			//readLine() that FileReader does not.
			in = new BufferedReader(new FileReader(f));
			String s = null;
			do {
				s = in.readLine();
				//readLine() returns null if there are no more lines, so check
				//that. Also, skip it if the line's first display character is
				//a '#'.
				if (s != null && !s.trim().substring(0, 1).equals("#")) {
					//If it passes both checks, print it to stdout.
					System.out.println(s);
				}
			} while (s != null);
		} catch (FileNotFoundException fnfe) {
			fnfe.printStackTrace();
		} catch (IOException ioe) {
			ioe.printStackTrace();
		}
	}
}

rpsls.rps

# Hashes mark comments and are ignored by the parser.
# You can probably figure out the format.
rock:
	crushes:scissors
	crushes:lizard
paper:
	covers:rock
	disproves:Spock
scissors:
	cut:paper
	stab:lizard
lizard:
	poisons:Spock
	eats:paper
Spock:
	smashes:scissors
	vaporises:rock
# Simple enough.