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从 Java 程序关闭特定 URL 的 Web 浏览器

IT小君   2021-11-15T13:55:21

我想关闭 Java 程序中特定 URL 的打开的 Web 浏览器/浏览器选项卡。我可以使用 Java 中的桌面 API 在 Internet Explorer 中打开 URL。

下面是在 IE 中打开浏览器的代码片段

java.awt.Desktop desktop = java.awt.Desktop.getDesktop();
desktop.browse(new java.net.URI("http://www.xyzz.com"));

现在，当我再次运行该程序时，我想确保没有在浏览器中打开上述 URL 的实例。如果是这样，请关闭它并在新的选项卡或浏览器窗口中再次打开它。这可能看起来有点奇怪的要求。

我知道解决这个问题的基本方法是，我们需要识别进程并杀死它，然后再次调用上面的代码。

欢迎任何建议。

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评论(2)
IT小君

我怀疑您可以使用 Desktop 做很多事情，因为您没有获得对启动过程的任何参考。

我过去曾使用过这种技术（在 Java 6 之前，Desktop 不存在）并且由于它与 Process 一起使用，您应该能够杀死它。

public static void openURL(String url) {
    StringBuilder sb = new StringBuilder();
    if (System.getProperty("os.name").indexOf("Windows")>-1) {
        String command = null;
        String urlLC = url.toLowerCase();
        if (urlLC.startsWith("https")) {
            command = WindowsCommandRetriever.getCommandForFileType("https");
        } else if (urlLC.startsWith("http")) {
            command = WindowsCommandRetriever.getCommandForFileType("http");
        }
        if (command == null) {
            command = WindowsCommandRetriever.commandForExtension(".html");
        }
        if (command.indexOf("%1") > -1) {
            sb.append(command.substring(0, command.indexOf("%1")));
            sb.append(url);
            sb.append(command.substring(command.indexOf("%1") + "%1".length()));
        } else {
            sb.append(command).append(' ');
            sb.append('"');
            sb.append(url);
            sb.append('"');
        }
    } else {
        sb.append("open ");
        sb.append(url);
    }
    try {
        final Process p = Runtime.getRuntime().exec(sb.toString());
        // Here you have the process. You can destroy it if you want
        // You need to figure out how you are going to handle this here.
    } catch (IOException e1) {
        e1.printStackTrace();
        System.err.println("Error while executing " + sb.toString());
    }
}

和 WindowsCommandRetriever：

/*
 * (c) Copyright 2010-2011 AgileBirds
 *
 * This file is part of OpenFlexo.
 *
 * OpenFlexo is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * OpenFlexo is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OpenFlexo. If not, see <http://www.gnu.org/licenses/>.
 *
 */

public class WindowsCommandRetriever {
    /**
     * 
     * @param extension
     *            the file extension (with or without the preceding '.')
     * @return the command to execute for the specified <code>extension</code> or null if there are no associated command
     */
    public static String commandForExtension(String extension) {
        String regKey = "HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\FileExts\\" + extension;
        String fileType = WinRegistryAccess.getRegistryValue(regKey, "ProgID", WinRegistryAccess.REG_SZ_TOKEN);
        if (fileType == null) {
            StringBuilder sb = new StringBuilder("cmd /C assoc ");
            sb.append(extension.startsWith(".") ? extension : "." + extension);

            ConsoleReader reader;
            try {
                Process process = Runtime.getRuntime().exec(sb.toString());
                reader = new ConsoleReader(process.getInputStream());
                reader.start();
                process.waitFor();
                reader.join();
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } catch (InterruptedException e) {
                e.printStackTrace();
                return null;
            }
            String result = reader.getResult();
            if (result.indexOf("=") > -1) {
                fileType = result.substring(result.indexOf("=") + 1).trim();
            }
        }
        if (fileType == null) {
            return null;
        }
        return getCommandForFileType(fileType);
    }

    public static String getCommandForFileType(String fileType) {
        String path = "HKEY_CLASSES_ROOT\\" + fileType + "\\shell\\open\\command";
        return WinRegistryAccess.getRegistryValue(path, null, WinRegistryAccess.REG_SZ_TOKEN);
    }
}


/*
 * (c) Copyright 2010-2011 AgileBirds
 *
 * This file is part of OpenFlexo.
 *
 * OpenFlexo is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * OpenFlexo is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OpenFlexo. If not, see <http://www.gnu.org/licenses/>.
 *
 */

import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;


public class WinRegistryAccess {

    private static final String REGQUERY_UTIL = "reg query ";

    public static final String REG_SZ_TOKEN = "REG_SZ";

    public static final String REG_BINARY = "REG_BINARY";

    public static final String REG_DWORD_TOKEN = "REG_DWORD";

    /**
     * Returns the value for an attribute of the registry in Windows. If you want to now the processor speed of the machine, you will pass
     * the following path: "HKLM\HARDWARE\DESCRIPTION\System\CentralProcessor\0" and the following attribute name: ~MHz
     * 
     * @param path
     *            - the registry path to the desired value
     * @param attributeName
     *            - the name of the attribute or null for the default
     * @param attributeType
     *            - the type of attribute (DWORD/SZ/...) default is REG_SZ
     * @return - the value for the attribute located in the given path
     */
    public static String getRegistryValue(String path, String attributeName, String attributeType) {
        if (attributeType == null) {
            attributeType = REG_SZ_TOKEN;
        }
        try {
            if (!path.startsWith("\"")) {
                path = "\"" + path + "\"";
            }
            StringBuilder sb = new StringBuilder();
            sb.append(REGQUERY_UTIL);
            sb.append(path);
            sb.append(' ');
            if (attributeName != null) {
                sb.append("/v ");
                sb.append(attributeName);
            } else {
                sb.append("/ve");
            }
            Process process = Runtime.getRuntime().exec(sb.toString());
            ConsoleReader reader = new ConsoleReader(process.getInputStream());
            reader.start();
            process.waitFor();
            reader.join();
            String result = reader.getResult();
            int p = result.indexOf(attributeType);
            if (p == -1) {
                return null;
            }
            return result.substring(p + attributeType.length()).trim();
        } catch (Exception e) {
            return null;
        }
    }

    public static class ConsoleReader extends Thread {
        private InputStream is;

        private StringWriter sw;

        ConsoleReader(InputStream is) {
            this.is = is;
            sw = new StringWriter();
        }

        @Override
        public void run() {
            try {
                int c;
                while ((c = is.read()) != -1) {
                    sw.write(c);
                }
            } catch (IOException e) {
                ;
            }
        }

        String getResult() {
            return sw.toString();
        }
    }

    public static String getJDKHome() {
        String key = "\"HKEY_LOCAL_MACHINE\\SOFTWARE\\JavaSoft\\Java Development Kit\"";
        String currentVersionAtt = "CurrentVersion";
        String javaHomeAtt = "JavaHome";
        String res1 = getRegistryValue(key, currentVersionAtt, null);
        String res2 = getRegistryValue(key + "\\" + res1, javaHomeAtt, null);
        return res2;
    }

    public static void main(String s[]) {
        String key = "\"HKEY_LOCAL_MACHINE\\SOFTWARE\\JavaSoft\\Java Development Kit\"";
        String currentVersionAtt = "CurrentVersion";
        String javaHomeAtt = "JavaHome";
        String res1 = getRegistryValue(key, currentVersionAtt, null);
        String res2 = getRegistryValue(key + "\\" + res1, javaHomeAtt, null);
        System.out.println("CurrentVersion '" + res1 + "'");
        System.out.println("JavaHome '" + res2 + "'");
    }
}
2021-11-15T13:55:21   回复
IT小君

这是不可能的，因为：

a.) 你不知道 desktop.browse() 启动了什么进程，

湾）你不知道其他人（）由浏览启动的进程可能是好的。

算了吧。即使你能以某种方式破解它，它也永远不会可靠地工作。

2021-11-15T13:55:21   回复