threads scanner

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1. package zad31;
2.  
3. import java.io.FileDescriptor;
4. import java.io.FileInputStream;
5. import java.util.concurrent.ExecutorService;
6. import java.util.concurrent.Executors;
7. import java.util.concurrent.TimeUnit;
8. import java.util.concurrent.locks.Lock;
9. import java.util.concurrent.locks.ReentrantLock;
10.  
11. import javax.swing.JOptionPane;
12.  
13. import com.sun.java_cup.internal.runtime.Scanner;
14.  
15. class Interruptible {
16.  
17.      Lock lock = new ReentrantLock();
18.  
19.      Runnable task1 = new Runnable() {
20.      public void run() {
21.      System.out.println("Task 1 begins");
22.      try {
23.      lock.tryLock(1000, TimeUnit.SECONDS); // próba zamknięcia rygla (czeka na wolny rygiel lub 1000 sekund)
24.      System.out.println("Task 1 entered");
25.      } catch(InterruptedException exc) {
26.      System.out.println("Task 1 interrupted");
27.      }
28.      System.out.println("Task 1 stopped");
29.      }
30.      };
31.  
32.      Runnable task2 = new Runnable() {
33.      public void run() {
34.      System.out.println("Task 2 begins");
35.      for (int i=1; i <= 600; i++) {
36.      if (Thread.currentThread().isInterrupted()) break;
37.      // jakieś obliczenie
38.      if (Thread.currentThread().isInterrupted()) break; // chcemy przerwać możliwie najszybciej
39.      try { // sleep() jest przerywane pzrez interrupt()!
40.      Thread.sleep(1000);
41.      } catch (InterruptedException exc) { break; }
42.      }
43.      System.out.println("Task 2 stopped");
44.      }
45.      };
46.  
47.  
48.      Runnable task3 = new Runnable() {
49.      Scanner scan = new Scanner( 
50.      new FileInputStream(FileDescriptor.in).getChannel(), "Cp852");
51.      public void run() {
52.      System.out.println("Task 3 begins");
53.      System.out.print(">>");
54.      while ((scan).hasNextLine()) {
55.      try {
56.      String s = scan.nextLine();
57.      System.out.print('\n'+s + "\n>>");
58.      } catch (Exception exc) {
59.      // Uwaga: scanner nie zgłasza wyjątków, ale przerywa dzialanie
60.      exc.printStackTrace();
61.      break;
62.      }
63.      }
64.      System.out.println("Task 3 stopped - " + scan.ioException()); // jaki wyjątek go przerwał?
65.      }
66.      };
67.  
68.      Interruptible() {
69.      ExecutorService exec = Executors.newCachedThreadPool();
70.  
71.      exec.execute(new Runnable() { // wątek zamyka rygiel
72.      public void run() {
73.      lock.lock();
74.      }
75.      }
76.      );
77.      exec.execute(task1);
78.      exec.execute(task2);
79.      exec.execute(task3);
80.      JOptionPane.showMessageDialog(null, "Press Ok to stop all tasks");
81.      exec.shutdownNow();
82.      }
83.  
84.     }
85.  
86.  
87.  

why eclipse says it cannot instantiate the type Scanner

Why not just use the scanner class in the util package

I'm almost sure the OP uses Java 1.5 or newer: the concurrent packages weren't
there in Java 1.4, or the OP must've installed Doug Lea's concurrent packages
manually which I don't believe for now.

When Eclipse doesn't recognize a class because you haven't imported it yet
or you haven't imported the entire package, Eclipse can search for it. When it
finds more than one candidate it offers a choice. Eclipse found a Scanner in
the com.sun.* package as well as the java.util package.

It is never sensible to *not* read the choices offered by Eclipse and simply
bang the enter key or to press the ok key. Reading is not (yet?) supposed to
be a lost ancient form of art you know.

kind regards,

Jos