Check format of URL

Question

I need a Java code which accepts an URL like http://www.example.com and displays whether the format of URL is correct or not.

adarshr · Accepted Answer · 2011-04-27T11:29:21.140

22

This should do what you're asking for.

public boolean isValidURL(String urlStr) {
    try {
      URL url = new URL(urlStr);
      return true;
    }
    catch (MalformedURLException e) {
        return false;
    }
}

Here's an alternate version:

public boolean isValidURI(String uriStr) {
    try {
      URI uri = new URI(uriStr);
      return true;
    }
    catch (URISyntaxException e) {
        return false;
    }
}

edited Apr 27 '11 at 11:29

answered Apr 27 '11 at 11:03

adarshr

61,315
23
138
167

1

use the [java.net.URI](http://download.oracle.com/javase/6/docs/api/java/net/URI.html) class instead. – McDowell Apr 27 '11 at 11:07
no guys it did not worked out can you please provide full code – Ram Apr 27 '11 at 15:39
1

@user what didn't work? YOU provide your code and show us what you have done so far. – adarshr Apr 27 '11 at 16:23
@adarshr Ok.I understand URL is a subset of URI but in context of this question why did you use URI as well? Won't URL be more specific? – Suvarna Pattayil Mar 17 '15 at 09:03
1

@Suvarna there's no particular reason. It is just a matter of taste. I was just demonstrating two different ways of solving the same problem. – adarshr Mar 17 '15 at 10:03
1

The "url" or "uri" local variable is not necessary. – Mark W Aug 23 '17 at 07:36
never use exception in nomral program flow. let thwor the exception is bad – dermoritz Dec 06 '19 at 08:49
According to version 1 (`URL`) "stackoverflow.com" is invalid, according to version 2 (`URI`) even nonsense like "---" is valid, so both versions aren't exactly great (unless you have to set up some type of pattern first?). I'd recommend using [Regex](https://stackoverflow.com/a/58578580/2016165) or Apache's [URLValidator](https://stackoverflow.com/a/5078838/2016165) instead. – Neph Mar 17 '20 at 14:18

Ruben Estrada · Answer 2 · 2019-03-08T01:22:17.093

Based on the answer from @adarshr I would say it is best to use the URL class instead of the URI class, the reason for it being that the URL class will mark something like htt://example.com as invalid, while URI class will not (which I think was the goal of the question).

//if urlStr is htt://example.com return value will be false
public boolean isValidURL(String urlStr) {
    try {
      URL url = new URL(urlStr);
      return true;
    }
    catch (MalformedURLException e) {
        return false;
    }
}

Check format of URL

2 Answers2