java - .zip 文件不会被删除，但也不会引发任何异常

Question

我已经创建了一个应用程序，其中包含我通常在电脑上使用的实用程序(例如将关机发送到 cmd.exe)，并且由于一些 friend 要求我将其提供给他们，我正在尝试添加一个更新系统来检查更新一个服务器，以便更轻松地始终更新其版本。

问题是，我一直在网上搜索任何解决方案，但所有解决方案都只是告诉使用 .close() 并且我的文件在停止需要它后就拥有了它。当我运行它时，一切正常并且没有抛出异常，所以我只是不知道会出现什么问题。

全类:

public class Main_Gui extends JFrame {

        private Thread worker;
        private final String root = "update/";

        private JTextArea outText;
        private JButton cancel;
        private JButton launch;
        private JScrollPane sp;
        private JPanel pan1;
        private JPanel pan2;

        private String zipFile = "Actualización.zip";
        private String path = "http://ritsu.hol.es/url.html";
        private String TITLE = "RitsUtilities | Actualizador";

        public Main_Gui() {
            initComponents();
            outText.setText("Conectando con el servidor...");
            download();
        }

        private void initComponents() {

            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (Exception e) {
                e.printStackTrace();
            }
            setTitle(TITLE);
            setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

            pan1 = new JPanel();
            pan1.setLayout(new BorderLayout());

            pan2 = new JPanel();
            pan2.setLayout(new FlowLayout());

            outText = new JTextArea();
            sp = new JScrollPane();
            sp.setViewportView(outText);

            launch = new JButton("Ejecutar RitsUtilities");
            launch.setEnabled(false);
            launch.addActionListener(new ActionListener() {

                public void actionPerformed(ActionEvent e) {
                    String[] run = { "java", "-jar", "RitsUtilities.jar" };
                    try {
                        Runtime.getRuntime().exec(run);
                    } catch (Exception ex) {
                        ex.printStackTrace();
                    }
                    System.exit(0);
                    launch();
                }
            });
            pan2.add(launch);

            cancel = new JButton("Salir");
            cancel.addActionListener(new ActionListener() {

                public void actionPerformed(ActionEvent e) {
                    System.exit(0);
                }
            });
            pan2.add(cancel);
            pan1.add(sp, BorderLayout.CENTER);
            pan1.add(pan2, BorderLayout.SOUTH);

            add(pan1);
            pack();
            setSize(500, 400);
            setLocationRelativeTo(null);

        }

        private void download() {

            worker = new Thread(new Runnable() {

                public void run() {
                    try {
                        downloadFile(getDownloadLinkFromHost());
                        unzip();
                        copyFiles(new File(root), new File("").getAbsolutePath());
                        cleanup();
                        launch.setEnabled(true);
                        outText.setText(outText.getText() + "\n¡Actualización completada con éxito!");
                    } catch (Exception e) {
                        e.printStackTrace();
                        JOptionPane.showMessageDialog(null, "Ha ocurrido un error al descargar y descomprimir la actualización.", "Error 1", JOptionPane.WARNING_MESSAGE);
                    }
                }
            });
            worker.start();
        }

        private void launch() {
            String[] run = { "java", "-jar", "update app.jar" };
            try {
                Runtime.getRuntime().exec(run);
            } catch (Exception ex) {
                ex.printStackTrace();
            }
            System.exit(0);
        }

        private void cleanup() {
            outText.setText(outText.getText() + "\nLimpiando archivos temporales...");
            remove(new File(root));
            new File(root).delete();
        }

        private void remove(File f) {
            File[] files = f.listFiles();
            for (File ff : files) {
                if (ff.isDirectory()) {
                    remove(ff);
                    ff.delete();
                } else {
                    ff.delete();
                }
            }

        }

        private void copyFiles(File f, String dir) throws IOException {
            File[] files = f.listFiles();
            for (File ff : files) {
                if (ff.isDirectory()) {
                    new File(dir + "/" + ff.getName()).mkdir();
                    copyFiles(ff, dir + "/" + ff.getName());
                } else {
                    copy(ff.getAbsolutePath(), dir + "/" + ff.getName());
                }

            }
        }

        public void copy(String srFile, String dtFile) throws FileNotFoundException, IOException {

            File f1 = new File(srFile);
            File f2 = new File(dtFile);

            InputStream in = new FileInputStream(f1);
            OutputStream out = new FileOutputStream(f2);

            byte[] buf = new byte[1024];
            int len;
            while ((len = in.read(buf)) > 0) {
                out.write(buf, 0, len);
            }
            in.close();
            out.close();
        }

        private void unzip() throws IOException {
            int BUFFER = 2048;
            BufferedOutputStream dest = null;
            BufferedInputStream is = null;
            ZipEntry entry;
            ZipFile zipfile = new ZipFile(zipFile);
            Enumeration e = zipfile.entries();
            (new File(root)).mkdir();
            while (e.hasMoreElements()) {
                entry = (ZipEntry) e.nextElement();
                outText.setText(outText.getText() + "\nExtrayendo: " + entry);
                if (entry.isDirectory())
                    (new File(root + entry.getName())).mkdir();
                else {
                    (new File(root + entry.getName())).createNewFile();
                    is = new BufferedInputStream(zipfile.getInputStream(entry));
                    int count;
                    byte data[] = new byte[BUFFER];
                    FileOutputStream fos = new FileOutputStream(root + entry.getName());
                    dest = new BufferedOutputStream(fos, BUFFER);
                    while ((count = is.read(data, 0, BUFFER)) != -1) {
                        dest.write(data, 0, count);
                    }
                    dest.flush();
                    dest.close();
                    is.close();
                }
            }

        }

        private void downloadFile(String link) throws MalformedURLException, IOException {
            URL url = new URL(link);
            URLConnection conn = url.openConnection();
            InputStream is = conn.getInputStream();
            long max = conn.getContentLength();
            outText.setText(outText.getText() + "\n" + "Descargando archivo...\nTamaño de la actualización(comprimida): " + max + " Bytes");
            BufferedOutputStream fOut = new BufferedOutputStream(new FileOutputStream(new File(zipFile)));
            byte[] buffer = new byte[32 * 1024];
            int bytesRead = 0;
            int in = 0;
            while ((bytesRead = is.read(buffer)) != -1) {
                in += bytesRead;
                fOut.write(buffer, 0, bytesRead);
            }
            fOut.flush();
            fOut.close();

            is.close();
            outText.setText(outText.getText() + "\n¡Descarga completada!");

        }

        private String getDownloadLinkFromHost() throws MalformedURLException, IOException {

            URL url = new URL(path);
            InputStream html = null;
            html = url.openStream();
            int c = 0;
            StringBuilder buffer = new StringBuilder("");

            while (c != -1) {
                c = html.read();
                buffer.append((char) c);
            }
            return buffer.substring(buffer.indexOf("[url]") + 5, buffer.indexOf("[/url]"));
        }

        public static void main(String args[]) {
            java.awt.EventQueue.invokeLater(new Runnable() {

                public void run() {
                    new Main_Gui().setVisible(true);
                }
            });
        }

    }

编辑:将private String zipFile = "Actualización.zip";更改为private String zipFile = "Update.zip";但仍然只是删除临时文件/目录，但不删除应用程序下载的“Update.zip”文件夹。

Answer 1

如果文件无法删除，您使用的 File#delete() 方法不会抛出错误，而是返回 false。这记录在 Javadoc 中，以及替代解决方案(强调我的):

Deletes the file or directory denoted by this abstract pathname. If this pathname denotes a directory, then the directory must be empty in order to be deleted.
Note that the Files class defines the delete method to throw an IOException when a file cannot be deleted. This is useful for error reporting and to diagnose why a file cannot be deleted.