comparing System.getProperty to string

[Mike Harris]

I'm trying to test whether the os is Windows XP by using the system.property("os.name") compared to a string "Windows XP". It is not working and I cannot figure out why. Can anyone point me in the right direction. My code is:

  import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
 
//read c:/b_conf.txt file
//within that file set path to: c:/apache2triad/htdocs/refresh/read_file
class rdFile{  
        public static void main(String args[]){
        long orig;
        String r="";
String s="";

System.out.println("prerun \n");

//read conf file
try {
String os = System.getProperty("os.name");
String cos = "Windows XP";
System.out.println(os);
System.out.println(cos);
if(os==cos){
File inputFile = new File("c:/b_conf.txt");
System.out.println("OS is windows");
}
System.out.println(System.getProperty("os.name"));

File inputFile = new File("c:/b_conf.txt");
 
        FileReader in = new FileReader(inputFile);
BufferedReader br = new BufferedReader(in);//BufferedReader puts info into ascii text


        int i=0;
s = br.readLine();
        System.out.println(s+"\n after s");
 
        } catch (IOException e) {}
        
    System.out.println("postrun");
 
           File f = new File(s);
           File[] files = f.listFiles();
for (int i=0;i<files.length;i++){
File nFile = files[i];
orig = nFile.lastModified();
System.out.println("last modifed date "+orig);
 
    }
}
}
 
  

[marc weber]

Instead of comparing values (references) using ==, try String's equals method for a more meaningful comparison.

if(os.equals(cos)) {...

[Layne Lund]

It looks like you need to read up on the difference between the equals() method and the == operator. This has been discussed many times on this forum, so you can use the Search Tool to find previous threads on the topic.

Layne