//jdk 1.4.x et inferieur
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
String lineSep = System.getProperty("line.separator");
String name = "fichier.txt";
try{
BufferedReader r = new BufferedReader(new FileReader(new File(name)));
String s = "";
String result = "";
while((s = r.readLine()) != null) result += (s+lineSep);
r.close();
System.out.println(result);
}catch(Exception e){
e.printStackTrace();
}
//jdk 1.5.x et superieur
import java.io.File;
import java.io.FileReader;
import java.util.Scanner;
String lineSep = System.getProperty("line.separator");
String name = "fichier.txt";
try{
String result = "";
Scanner s = new Scanner(new FileReader(new File(name)));
while(s.hasNext())result += (s.nextLine() + lineSep);
System.out.println(result);
}catch(Exception e){
e.printStackTrace();
}