从javascript调用时，签名的小程序提供AccessControlException：访问被拒绝

Question

我有一个简单的自签名小程序（使用keytool和jarsigner完成）：

public class NetAppletLauncher extends JApplet {

    private static final long serialVersionUID = 1L;

    public void init() {
        exec("notepad c:/hello.txt");
    }

    public void exec(String command) {

        try {

            // launch EXE and grab stdin/stdout and stderr
            Process process = Runtime.getRuntime().exec(command);
            //      OutputStream stdin = process.getOutputStream();
            InputStream stderr = process.getErrorStream();
            InputStream stdout = process.getInputStream();

            // "write" the parms into stdin
//          stdin.write(arguments.getBytes());
//          stdin.flush();
//          stdin.close();

            // clean up if any output in stdout
            String line = "";
            BufferedReader brCleanUp = new BufferedReader(new InputStreamReader(stdout));
            while ((line = brCleanUp.readLine()) != null) {
                //System.out.println ("[Stdout] " + line);
            }
            brCleanUp.close();

            // clean up if any output in stderr
            brCleanUp = new BufferedReader(new InputStreamReader(stderr));
            while ((line = brCleanUp.readLine()) != null) {
                //System.out.println ("[Stderr] " + line);
            }
            brCleanUp.close();

        } catch (Exception exception) {
            exception.printStackTrace();
        }

    }

}

基本上，它的作用是执行“记事本c：/hello.txt”。

然后，我将小程序嵌入html：

<applet id='applet' name='applet' archive='NetAppletLauncher1.jar' code='src.NetAppletLauncher' width='100' height='100' MAYSCRIPT ></applet>

当我访问页面时，JRE启动并询问我是否要启动此applet，以及是否信任它。我按确定。然后记事本开始-应该。没问题

但是，然后我将其添加到HTML页面：

<p class="link" onclick="document.applet.exec('calc');">remote desktop2</p>

现在，当我按此文本时，calc应该开始-对吗？但这给了我：

java.security.AccessControlException: access denied (java.io.FilePermission <<ALL FILES>> execute)
    at java.security.AccessControlContext.checkPermission(Unknown Source)

• 这是怎么回事？为什么现在给我一个安全例外，但它可以在以前启动记事本？

Answer 1

解决了Java中的问题：

exec(getParameter("command"));

然后在JavaScript中：

<script type="text/javascript">

function exec( command ) {

    var applet = "<applet id='applet' style='visibility: hidden' name='applet' archive='NetAppletLauncher4.jar' code='src.NetsetAppletLauncher' width='20' height='20' MAYSCRIPT ><param name='command' value='" + command + "' />Sorry, you need a Java-enabled browser.</applet>";

    var body = document.getElementsByTagName("body")[0];
    var div = document.createElement("div");
    div.innerHTML = applet;
    body.appendChild(div);

}

</script>