ДЗ Загрузка файлов в потоках.

Lesson1/src/network/HttpDownload.java

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+package network;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.util.concurrent.Semaphore;
+
+public class HttpDownload {
+    private static final int BUFFER_SIZE = 4096;
+
+    public static void downloadFile(String fileURL, String saveDir) throws IOException {
+
+        URL url = new URL(fileURL);
+        HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
+        int responseCode = httpConn.getResponseCode();
+
+        if (responseCode == HttpURLConnection.HTTP_OK) {
+
+            String fileName = fileURL.substring(fileURL.lastIndexOf("/") + 1);
+            String saveFilePath = saveDir + File.separator + fileName;
+
+            InputStream inputStream = httpConn.getInputStream();
+            FileOutputStream outputStream = new FileOutputStream(saveFilePath);
+
+            int bytesRead = -1;
+            byte[] buffer = new byte[BUFFER_SIZE];
+
+            while ((bytesRead = inputStream.read(buffer)) != -1) {
+                outputStream.write(buffer, 0, bytesRead);
+            }
+
+            outputStream.close();
+            inputStream.close();
+
+            System.out.println("Файл " + fileName + " загружен!");
+        } else {
+            System.out.println("Ошибка загрузки. Код сервера : " + responseCode);
+        }
+        httpConn.disconnect();
+    }
+
+}
+
+class DownloadtThread implements Runnable {
+    Semaphore sem;
+    String url;
+    String destinationFile;
+
+    public DownloadtThread(String url, Semaphore sem, String destinationFile) {
+        this.sem = sem;
+        this.url = url;
+        this.destinationFile = destinationFile;
+    }
+
+    @Override
+    public void run() {
+        try {
+            sem.acquire();
+            HttpDownload.downloadFile(url, destinationFile);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        sem.release();
+    }
+}

Lesson1/src/network/TestDownload.java

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+package network;
+
+import java.util.concurrent.Semaphore;
+
+public class TestDownload {
+
+    public static void main(String[] args) throws Exception {
+
+        Semaphore sem = new Semaphore(2);
+
+        String imageUrl = "https://catspaw.ru/wp-content/uploads/2017/03/Seryiy-kot-Daniel-Felicia.jpg";
+        String destinationFile = "C:/TEMP";
+        new Thread(new DownloadtThread(imageUrl, sem, destinationFile)).start();
+        imageUrl = "https://static.probusiness.io/720x480c/n/03/d/38097027_439276526579800_2735888197547458560_n.jpg";
+        new Thread(new DownloadtThread(imageUrl, sem, destinationFile)).start();
+        imageUrl = "https://cdn2.img.ria.ru/images/148393/86/1483938656.jpg";
+        new Thread(new DownloadtThread(imageUrl, sem, destinationFile)).start();
+        imageUrl = "https://icdn.lenta.ru/images/2018/09/07/09/20180907092850529/pic_32874ef1a26ef118dd32a33a72f277af.jpg";
+        new Thread(new DownloadtThread(imageUrl, sem, destinationFile)).start();
+
+    }
+
+}