java - 从 Javascript 调用的 Applet 方法

Question

我有一个小程序可以从特定文件夹上传一些文件并删除它们，但是当我从我的 javascript 代码调用小程序函数时，当我从 init() 调用该函数时出现了问题工作正常。

我的小程序代码:

public class Uploader extends Applet {
   String serverPath;
   String clientPath;
   private JSObject win;
   @Override
   public void init() {
       serverPath = getParameter("serverPath");
       clientPath = getParameter("clientPath");
       try {
           win = JSObject.getWindow(this);
       } catch (JSException e) {
           log.warning("Can't access JSObject object");
       }
       upload(topic,clientPath);
   }
   public void upload(String topic,String clientPath) {
       log.log(Level.SEVERE, "upload functiond");
       DefaultHttpClient client = new DefaultHttpClient();
       MultipartEntity form = new MultipartEntity();
       log.log(Level.SEVERE, "upload functiond2");
       try {
            File directory = new File(clientPath);
            log.log(Level.SEVERE, "upload functiond2.2");
            File[] files = directory.listFiles();
            log.log(Level.SEVERE, "upload functiond2.5");
            int i = 0;
            for (File file : files) {
                log.log(Level.SEVERE, "upload functiond2.6");
                i++;
                form.addPart("file" + String.valueOf(i), new FileBody(file));
                System.out.println("adding file " + String.valueOf(i) + " " + file);
                log.log(Level.SEVERE, "adding file " + String.valueOf(i) + " " + file);
            }
            log.log(Level.SEVERE, "upload functiond3");
            form.addPart("topic", new StringBody(topic, Charset.forName("UTF-8")));
            form.addPart("action", new StringBody(action, Charset.forName("UTF-8")));
            form.addPart("path", new StringBody(serverPath, Charset.forName("UTF-8")));
            HttpPost post = new HttpPost(serverPath);
      ....

这是我的 javascript 代码:

document.applet.upload(title,"c:\scan");

当我从 javascript 调用时只打印日志:

log.log(Level.SEVERE, "upload functiond2.2");

请注意，当我从 applet 的 init 方法调用时，它工作正常。

我将我的代码包装到 PriviligedAction 中，但只向前迈出一步并坚持

log.log(Level.SEVERE, "upload functiond2.5");

Answer 1

Java 和 JS 的交互使安全性变得复杂。 JRE 不能信任 JS，因此它决定包括您的代码的整个“操作链”是不受信任的。有一种方法可以修复它。

代码需要包裹在PrivilegedAction中并使用 AccessController methods 之一调用doPrivileged(..)。查看 AccessController 文档的顶部。 (在方法上方)查看示例用法。