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POHow to check if a URL exists or returns 404 with Java?
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copied!<pre><code>String urlString = "http://www.nbc.com/Heroes/novels/downloads/Heroes_novel_001.pdf"; URL url = new URL(urlString); if(/* Url does not return 404 */) { System.out.println("exists"); } else { System.out.println("does not exists"); } urlString = "http://www.nbc.com/Heroes/novels/downloads/Heroes_novel_190.pdf"; url = new URL(urlString); if(/* Url does not return 404 */) { System.out.println("exists"); } else { System.out.println("does not exists"); } </code></pre> <p>This should print</p> <pre><code>exists does not exists </code></pre> <p><strong>TEST</strong></p> <pre><code>public static String URL = "http://www.nbc.com/Heroes/novels/downloads/"; public static int getResponseCode(String urlString) throws MalformedURLException, IOException { URL u = new URL(urlString); HttpURLConnection huc = (HttpURLConnection) u.openConnection(); huc.setRequestMethod("GET"); huc.connect(); return huc.getResponseCode(); } System.out.println(getResponseCode(URL + "Heroes_novel_001.pdf")); System.out.println(getResponseCode(URL + "Heroes_novel_190.pdf")); System.out.println(getResponseCode("http://www.example.com")); System.out.println(getResponseCode("http://www.example.com/junk")); </code></pre> <p>Output</p> <p>200<br> 200<br> 200<br> 404</p> <h1>SOLUTION</h1> <p>Add the next line before .connect() and the output would be 200, 404, 200, 404</p> <pre><code>huc.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 (.NET CLR 3.5.30729)"); </code></pre>

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