CompareTo method to compare files

Question

I have to compare each line from two files and say whether the lines are different or not. I don't exactly understand how to use the compareTo method in this type of situation. I'd appreciate any help.
import java.util.*;
import java.io.*;
import java.net.*;
import java.util.StringTokenizer;
public class FileComparer
public static void main (String[] args)
String line, file="http://condor.depaul.edu/~jpetlick/extra/224/display.txt";
String line2, file2="http://condor.depaul.edu/~jpetlick/extra/224/display2.txt";
int lineCount = 0, wordCount = 0, lineCounter = 0;
try
URL URLfile = new URL (file);
InputStream input = URLfile.openStream();
BufferedReader buffer = new BufferedReader(new InputStreamReader(input));
line = buffer.readLine();
URL URLfile2 = new URL (file2);
InputStream input2 = URLfile2.openStream();
BufferedReader buffer2 = new BufferedReader(new InputStreamReader(input2));
line2 = buffer2.readLine();
while (line != null)
if (line != line2)
System.out.println("at Line " + lineCounter);
System.out.println("DISPLAY.TXT " + line);
System.out.println("DISPLAY2.TXT " + line2);
lineCounter++;
StringTokenizer st = new StringTokenizer(line);
wordCount += st.countTokens();
lineCount++;
line = buffer.readLine();
line2 = buffer2.readLine();
System.out.println("\nA total of " + lineCounter + " were different between DISPLAY.TXT and DISPLAY2.TXT");
System.out.println("DISPLAY.TXT contains:");
System.out.println("\nTotal number of lines: " + lineCount);
System.out.println("Total number of words: " + wordCount);
catch (FileNotFoundException exception)
System.out.println("The file " + file + " was not found.");
catch (IOException exception)
System.out.println(exception);
}

Answer 1

Change the lineif (line != line2)to if (!line.equals( line2))since strings are immutable in java "line != line2" will alwais evaluate to false in your case.
equals actually compares the contents of the string.
Kurt.