Homework 10

org/geekhub/ConnectionUtils.java

@@ -1,6 +1,6 @@
 package org.geekhub;
 
-import java.io.IOException;
+import java.io.*;
 import java.net.URL;
 
 /**
@@ -16,7 +16,17 @@ public class ConnectionUtils {
      * @throws IOException
      */
     public static byte[] getData(URL url) throws IOException {
-        //implement me
-        return null;
+        ByteArrayOutputStream data = new ByteArrayOutputStream();
+
+        try (BufferedInputStream inputStream = new BufferedInputStream(url.openStream())) {
+            byte[] buffer = new byte[1024];
+            int bytesRead;
+
+            while ((bytesRead = inputStream.read(buffer)) != -1) {
+                data.write(buffer, 0, bytesRead);
+            }
+        }
+
+        return data.toByteArray();
     }
 }

org/geekhub/ImageCrawler.java

@@ -5,6 +5,7 @@
 import java.net.URL;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.regex.Pattern;
 
 /**
  * ImageCrawler downloads all images to specified folder from specified resource.
@@ -19,6 +20,8 @@ public class ImageCrawler {
     private ExecutorService executorService = Executors.newFixedThreadPool(NUMBER_OF_THREADS);
     private String folder;
 
+    Pattern imagePattern = Pattern.compile("([^\\s]+(\\.(?i)(jpg|png|gif|bmp))$)");
+
     public ImageCrawler(String folder) throws MalformedURLException {
         this.folder = folder;
     }
@@ -29,7 +32,14 @@ public ImageCrawler(String folder) throws MalformedURLException {
      * @throws IOException
      */
     public void downloadImages(String urlToPage) throws IOException {
-        //implement me
+        URL url = new URL(urlToPage);
+
+        if (isImageURL(url)) {
+            executorService.submit(new ImageTask(url, folder));
+        } else {
+            new Page(url).getImageLinks().stream()
+                    .forEach((URL link) -> executorService.submit(new ImageTask(link, folder)));
+        }
     }
 
     /**
@@ -41,8 +51,7 @@ public void stop() {
 
     //detects is current url is an image. Checking for popular extensions should be enough
     private boolean isImageURL(URL url) {
-        //implement me
-        return false;
+        return imagePattern.matcher(url.toString()).matches();
     }
 
 

org/geekhub/ImageTask.java

@@ -1,6 +1,10 @@
 package org.geekhub;
 
+import java.io.IOException;
 import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 
 /**
  * Represents worker that downloads image from URL to specified folder.<br/>
@@ -20,7 +24,13 @@ public ImageTask(URL url, String folder) {
      */
     @Override
     public void run() {
-       //implement me
+        Path path = Paths.get(folder + "/" + buildFileName(url));
+
+        try {
+            Files.write(path, ConnectionUtils.getData(url));
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
     }
 
     //converts URL to unique file name

org/geekhub/Page.java

@@ -12,8 +12,8 @@
  * Allows high-level access to page elements.
  */
 public class Page {
-    Pattern linkPattern = Pattern.compile("<a\\s(?:[^\\s>]*?\\s)*?href=\"(.*?)\".*?>");
-    Pattern imageLinkPattern = Pattern.compile("<img.*?src=\"(.*?)\".*?(/>|</img>)");
+    Pattern linkPattern = Pattern.compile("<a\\s(?:[^\\s>]*?\\s)*?href=\"(https?.*?)\".*?>");
+    Pattern imageLinkPattern = Pattern.compile("<img.*?src=\"(.*?)\".*?(/>|)");
 
     private String content;
     private URL url;