java - 取消 SwingWorker 的问题

Question

我正在制作一个旨在作为备份的程序。我让 SwingWorker 执行备份并将它正在执行的操作发布到 JTextArea。我想要一个按钮来取消 worker ，(一次初始化的数量未知)所以这就是我调用 Swing worker 的方法，以及取消方法:

package main;

import java.io.File;
import java.util.ArrayList;

import javax.swing.SwingWorker;

public class test2 {

SwingWorker bw;
static ArrayList bgWorker = new ArrayList();
ArrayList al = new ArrayList(); // this is the list of files selected
static boolean bwInitiallized = false;

public void startBackup() throws Exception {
    Panel.txtArea.append("Starting Backup...\n");

    for (int i = 0; i < al.size(); i++) {
        /**
         * THIS IS WHERE I NEED TO CREATE THE FOLDER THAT EACH BACKUP FILE
         * WILL GO INTO EX: SC2 GOES INTO A FOLDER CALLED SC2 AND RIOT GOES
         * TO RIOT, ALL WITHIN THE DIRECTORY CHOSEN
         */
        File file = new File((String) al.get(i));
        File directory = new File(dir); // dir is gotten by a JFileChooser.

        bw = new BackgroundWorker(Panel.txtArea, file, directory);
        bgWorker.add(bw);
        bwInitiallized = true;
        bw.execute();

        /**
         * follows to the bottom of the txtarea
         */
        int x;
        Panel.txtArea.selectAll();
        x = Panel.txtArea.getSelectionEnd();
        Panel.txtArea.select(1, x);
    }
}

public static void cancel() {
    BackgroundWorker bg;

    if (bwInitiallized) {
        bwInitiallized = false;
        Panel.txtArea.append("Cancelling...\n");
        for (int i = 0; i < bgWorker.size(); i++) {
            bg = (BackgroundWorker) bgWorker.get(i);
            bg.cancel(true);
        }
        Panel.txtArea.append("Canceled backUp!\n");
    } else {
        Panel.txtArea.append("Cannot Cancel! Not Initiallized!\n");
    }
}
}

好吧，由于我无法弄清楚的原因，这并没有取消它们中的任何一个(据我所知)。我唯一能想到的就是当我做的时候

bg = (BackgroundWorker) bgWorker.get(i);
bg.cancel(true);

它并没有像我想的那样做，但是 idk。我究竟做错了什么？提前致谢!

Answer 1

我会创建一个 class FileWorker extends SwingWorker<File, File> 的实例对于每个文件和 class Supervisor extends SwingWorker<Queue<File>, File> 的单个实例按照本 example 中的建议管理它们.您可以允许用户取消个人 FileWorker或者让 Supervisor全部取消。使用 cancel() 的示例显示 here .

无论如何，请使用适当的 SwingWorker按照@Hovercraft 评论中的建议，为安全输入参数并严格检查您的设计。