converting InetAddress to string

Question

Im using a hashtable to save filename (string) and InetAddress

Hashtable <String , InetAddress > file_location = new Hashtable <String , InetAddress >();

and im using this to retrieve the address, but im only getting a null value returned

file_location.put("ABD_9158" , IPAddress); //IPAdress is of InetAddress type

 InetAddress n = file_location.get("ABD_9158");

        System.out.println(n);

tried changing n to a string but , havent been able to find away my question, how do retrieve the ipaddress ?

you can run your program in debug mode and inspect the state of your map. If actually there is a key `ABD_9158` or any value corresponding to it. — Shailesh Aswal, Nov 20 '14 at 05:24
@Amr Hamada try print your `HashMap`, `System.out.println(fileLocation );` — Ankur Singhal, Nov 20 '14 at 05:26
when i use enumerate e = file_location.key(); and print that, it returns ABD_9158 — Amr Hamada, Nov 20 '14 at 05:27
You have declared as fileLocation but used file_location afterwards. Hope this is not how the code is actually. — Sach, Nov 20 '14 at 05:35
@Sachini nope its actually file_location through out my code, i didnt copy and paste, thats why i messed up — Amr Hamada, Nov 20 '14 at 05:37
Also you need the new Hashtable initialization should end with `()`. — Sach, Nov 20 '14 at 05:39
Assuming your IP address is not null because of a bug of the code somewhere else, it might be a good idea to use `String.valueOf(n)` because n is not actually a String. This is a good practise and I don't think is the actual error though — Sach, Nov 20 '14 at 05:42

score 0 · Accepted Answer · answered Nov 20 '14 at 05:37

0

This is a small program, to check what you want. Same piece of code, what you have shared, it is working fine.

 public static void main(String args[]) {
        Hashtable<String, InetAddress> fileLocation = new Hashtable<String, InetAddress>();
        InetAddress addr;
        try {
            addr = InetAddress.getByName("127.0.0.1");
            fileLocation.put("ABD_9158", addr); // IPAdress is of InetAddress type
            InetAddress n = fileLocation.get("ABD_9158");
            System.out.println(n);
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }

Output

/127.0.0.1

answered Nov 20 '14 at 05:37

Ankur Singhal

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yes actually when i used the the variable instead of "ABD_9158" i got the address return correctly , do u know why this might be happening. i am a hundred percent sure im writing correctly and matching it to the variable? – Amr Hamada Nov 20 '14 at 05:42
i compared both strings, the variable and the string "ABD_9158" and for some reason theyre not the same – Amr Hamada Nov 20 '14 at 05:51
@AmrHamada are you using `==` or `equals` to compare, the later will give you correct result, incase you are missing on that – Ankur Singhal Nov 20 '14 at 05:54
no i was using `equals` when that didnt work i also used `equalsIgnoreCase`, if this helps im actually sending the file name through a datagram socket and recieving the file with this line `String file = new String( receivePacket.getData());` – Amr Hamada Nov 20 '14 at 06:02

converting InetAddress to string

1 Answers1