// ui/InterruptableLongRunningCallable.java

// (c)2016 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://mindviewinc.com/Books/OnJava/ for more book information.

// Using Callables for long-running tasks

import javax.swing.*;

import java.awt.*;

import java.util.concurrent.*;

import onjava.*;

import static onjava.SwingConsole.*;

class CallableTask extends Task

implements Callable<String> {

@Override

public String call() {

run();

return "Return value of " + this;

}

}

public class

InterruptableLongRunningCallable extends JFrame {

private JButton

b1 = new JButton("Start Long Running Task"),

b2 = new JButton("End Long Running Task"),

b3 = new JButton("Get results");

private TaskManager<String,CallableTask> manager =

new TaskManager<>();

public InterruptableLongRunningCallable() {

b1.addActionListener(e -> {

CallableTask task = new CallableTask();

manager.add(task);

System.out.println(task + " added to the queue");

});

b2.addActionListener(e -> {

for(String result : manager.purge())

System.out.println(result);

});

b3.addActionListener(e -> {

// Sample call to a Task method:

for(TaskItem<String,CallableTask> tt : manager)

tt.task.id(); // No cast required

for(String result : manager.getResults())

System.out.println(result);

});

setLayout(new FlowLayout());

add(b1);

add(b2);

add(b3);

}

public static void main(String[] args) {

run(new InterruptableLongRunningCallable(), 200, 150);

}

}