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POdownloading images from reddit with java errors
 

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  1. POdownloading images from reddit with java errors
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    <p>So I have been googling how to download images and not getting very well written explanations, just code examples. I don't completely understand some of this code, mainly with the</p> <pre><code> for (int b; (b = is.read()) != -1;) { os.write(b); } </code></pre> <p>Can someone explain this above code like I am five, and also any alternatives to this method.</p> <p>EDIT2</p> <pre><code>import java.io.BufferedOutputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.MalformedURLException; import java.net.URL; import org.jsoup.Jsoup; import org.jsoup.nodes.Document; import org.jsoup.nodes.Element; import org.jsoup.select.Elements; public class Downloader { static String path = "C:\\reddit\\"; public static void main(String[] args) { connect(); } private static void download(String imageURL, int i) { InputStream is = null; OutputStream os = null; try { URL url = new URL(imageURL); is = url.openStream(); os = new FileOutputStream(path + i + ".jpg"); for (int b; (b = is.read()) != -1;) { os.write(b); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { if (is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } if (os != null) { try { os.close(); } catch (IOException e) { e.printStackTrace(); } } } } public static void connect() { try { Document doc = Jsoup.connect("http://www.reddit.com/r/pics").get(); Elements url = doc.select("a"); int i = 0; for (Element img : url) { if (img.attr("href").startsWith("http://imgur.com/")) { String image = img.attr("abs:href")+".jpg"; System.out.println(image); i++; System.out.println(i); download(image, i); } } } catch (IOException e) { System.out.println("page scrape fail"); } } </code></pre> <p>}</p> <p>EDIT I noticed my output is not right, its writing duplicates, I will just post my console result</p> <pre><code>http://imgur.com/f7rW2Of 1 http://imgur.com/f7rW2Of 2 http://imgur.com/35jpkez 3 http://imgur.com/35jpkez 4 http://imgur.com/IX9HMJG 5 http://imgur.com/IX9HMJG 6 http://imgur.com/B6MoDbT 7 http://imgur.com/B6MoDbT 8 http://imgur.com/XMtCUY9 9 http://imgur.com/XMtCUY9 10 http://imgur.com/UkbbiBl 11 http://imgur.com/UkbbiBl 12 http://imgur.com/YfLsCal 13 http://imgur.com/YfLsCal 14 http://imgur.com/9Q3CJtT 15 http://imgur.com/9Q3CJtT 16 http://imgur.com/Vt7sWTf 17 http://imgur.com/Vt7sWTf 18 http://imgur.com/hBUH5kS 19 http://imgur.com/hBUH5kS 20 http://imgur.com/gallery/OWQH0h6 21 http://imgur.com/gallery/OWQH0h6 22 http://imgur.com/a/hiJXI 23 http://imgur.com/a/hiJXI 24 </code></pre>
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    1. COShow an actual error. And yes, aside from the inefficiency of reading one byte at a time, you are looking OK.
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      1. USMad Physicist
    2. CODo you mean reading 1 byte at a time because of BufferedReader? I just deleted this and I still see no change. Each file is 29-35kb, none are able to view even if I change to jpg. I have no error any more, I can download all 27 images from the reddit.com/r/pics page, just can't view any of them. Can you eli5 the actual writing part
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      1. USgallly
    3. COAre they all JPG?
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      1. USMad Physicist
 

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