task2606

Author: SkyrocketStan

3.JavaMultithreading/src/com/javarush/task/task26/task2606/Solution.java

@@ -0,0 +1,113 @@
+package com.javarush.task.task26.task2606;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.*;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+
+/* 
+Тот, кто любит труд, не нуждается в развлечениях
+*/
+
+public class Solution {
+    private final URL javarushUrl;
+    private final URL javarushUrl1Child;
+    private final URL javarushVkGroupUrl;
+    private final URL javarushVkGroupUrl1Child;
+    private final URL javarushVkGroupUrl2Child;
+    private final URL javarushVkGroupUrl3Child;
+
+    private volatile ExecutorService executorService;
+    private final Set<URL> urlsForProcessing = Collections.synchronizedSet(new HashSet<>());
+
+    public static void main(String[] args) throws MalformedURLException, InterruptedException {
+        Solution solution = new Solution();
+        solution.start();
+        Thread.sleep(1000);
+        solution.stop();
+    }
+
+    public Solution() throws MalformedURLException {
+        javarushUrl = new URL("http://javarush.ru/");
+        javarushVkGroupUrl = new URL("http://vk.com/javarush");
+        javarushUrl1Child = new URL("http://info.javarush.ru/page/FAQ/");
+        javarushVkGroupUrl1Child = new URL("https://plus.google.com/114772402300089087607/about");
+        javarushVkGroupUrl2Child = new URL("https://www.facebook.com/pages/Javarush/524321077686033");
+        javarushVkGroupUrl3Child = new URL("https://twitter.com/javarush_ru");
+
+        urlsForProcessing.add(javarushUrl);
+        urlsForProcessing.add(javarushVkGroupUrl);
+    }
+
+    public synchronized void start() {
+        executorService = Executors.newCachedThreadPool();
+        for (URL url : urlsForProcessing) {
+            submitUrlTask(url);
+        }
+        urlsForProcessing.clear();
+    }
+
+    public synchronized void stop() throws InterruptedException {
+        try {
+            saveUnprocessedUrls(executorService.shutdownNow());
+            if (executorService.awaitTermination(1_000, TimeUnit.MILLISECONDS)) {
+                saveUnprocessedUrls(getCancelledTasksFromExecutor());
+            }
+        } finally {
+            executorService = null;
+        }
+    }
+
+    private List<Runnable> getCancelledTasksFromExecutor() {
+        return Collections.EMPTY_LIST;
+    }
+
+    protected List<URL> processPage(URL url) {
+        System.out.println(url + " will be processed");
+        return getChildUrlByParent(url);
+    }
+
+    private List<URL> getChildUrlByParent(URL url) {
+        List<URL> result = new ArrayList<>();
+
+        if (javarushUrl.equals(url)) {
+            result.add(javarushUrl1Child);
+        } else if (javarushVkGroupUrl.equals(url)) {
+            result.add(javarushVkGroupUrl1Child);
+            result.add(javarushVkGroupUrl2Child);
+            result.add(javarushVkGroupUrl3Child);
+        }
+        return result;
+    }
+
+    private void saveUnprocessedUrls(List<Runnable> unprocessed) {
+        for (Runnable task : unprocessed) {
+            urlsForProcessing.add(((UrlTask) task).getPage());
+        }
+    }
+
+    private void submitUrlTask(URL url) {
+        executorService.execute(new UrlTask(url));
+    }
+
+    public class UrlTask implements Runnable {
+        private final URL url;
+
+        private UrlTask(URL url) {
+            this.url = url;
+        }
+
+        public void run() {
+            for (URL link : processPage(url)) {
+                if (Thread.currentThread().isInterrupted()) return;
+                submitUrlTask(link);
+            }
+        }
+
+        public URL getPage() {
+            return url;
+        }
+    }
+}