Applet AccessControlException

[Kedar Dravid]

I am trying to store a file on the server. I am using an applet to capture video streams from a web-cam and store the files on the server every 10 minutes. But I am getting the following exception:
java.security.AccessControlException: access denied (java.io.FilePermission C:\temp read)
I created a policy file

  
 
import javax.media.*;
import javax.media.format.AudioFormat;
import javax.media.format.RGBFormat;
import javax.media.format.VideoFormat;
import javax.media.format.YUVFormat;
import javax.media.protocol.DataSource;
import javax.media.protocol.FileTypeDescriptor;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
 
public class SenderApplet extends Applet implements Runnable, ActionListener {
    Button startButton = null;
    Button stopButton = null;
    GridBagLayout gridbag = null;
 
    private static int TIME_EACH_CLIP = 5000; // in miliseconds
 
    // Change the default format string by selecting one of the formats supported by your camera
    // To List all the formats supported make debug=true
    private static String defaultVideoFormatString = "size=352x288, encoding=rgb, maxdatalength=152064";
    private static String defaultAudioFormatString = "linear, 8000.0 hz, 8-bit, mono, unsigned";
    private boolean debug = false;
 
//A CaptureDeviceInfo object contains information about a particular capture device. 
    private static CaptureDeviceInfo captureVideoDevice = null;
    private static CaptureDeviceInfo captureAudioDevice = null;
 
//Encapsulates format information for video data. The attributes of a VideoFormat include the encoding type, frame size, //frame rate, and the data type. 
    private static VideoFormat captureVideoFormat = null;
    private static AudioFormat captureAudioFormat = null;
 
    //Processor processor = null;
//A Format abstracts an exact media format. It carries no encoding-specific parameters or timing information global to the //presentation. 
 

    Format[] audioVideoOutputFormat = new Format[2];
    Format[] audioOutputFormat = new Format[1];
    Format[] videoOutputFormat = new Format[1];
//This sub-class of ContentDescriptor enumerates those content descriptors that are file formats. That is, data of this //content type can be saved to a file. It helps differentiate from content types that are not file formats.
    FileTypeDescriptor outputType = null;
    private Processor processor = null;
 
    // Get these parameters from applet parameters
    private String localDirectory = "C:\\temp\\";
    private String baseFileName = "safexmas"; //must be unique to user.(userid)
    private int counter = 0; //read from the jsp page
    private String uploadURL = "c:/VConf/parserUpload.jsp"; //Default Value
 
    private DataSink filewriter = null;
    boolean continueCapture = false;
    Thread runThread = null;
 

    public void init() {
       /* try {
            new MySecurityManager();
        } catch (Exception e) {
        e.printStackTrace();
        }*/
        counter = Integer.parseInt(getParameter("counter"));
System.out.println("counter === " + counter);
        baseFileName = getParameter("sender");
System.out.println("baseFileName === " + baseFileName);
        uploadURL = getParameter("uploadurl");
System.out.println("uploadURL === " + uploadURL);
        localDirectory = getParameter("localdirectory");
System.out.println("localDirectory === " + localDirectory);
        this.buildUI();
 
//CaptureDeviceManager is a manager class that provides access to a list of the capture devices available on a system. //CaptureDeviceManager uses a registry and query mechanisms to locate devices and return CaptureDeviceInfo objects for //available devices. The CaptureDeviceManager is also used to register new capture devices.
        java.util.Vector deviceListVector = CaptureDeviceManager.getDeviceList(null);
System.out.println("deviceListVector === " + deviceListVector);
        if (deviceListVector == null) {
            System.exit(0);
        }
        for (int x = 0; x < deviceListVector.size(); x++) {
            CaptureDeviceInfo deviceInfo = (CaptureDeviceInfo) deviceListVector.elementAt(x);
System.out.println("deviceInfo === " + deviceInfo);      
            Format deviceFormat[] = deviceInfo.getFormats();
            for (int y = 0; y < deviceFormat.length; y++) {
                if ((captureVideoDevice == null) && (deviceFormat[y] instanceof VideoFormat))
                    captureVideoDevice = deviceInfo;
                if ((captureVideoDevice == deviceInfo) && (captureVideoFormat == null) && (DeviceInfo.formatToString(deviceFormat[y]).indexOf(defaultVideoFormatString) >= 0))
                    captureVideoFormat = (VideoFormat) deviceFormat[y];
                if ((captureAudioDevice == null) && (deviceFormat[y] instanceof AudioFormat))
                    captureAudioDevice = deviceInfo;
                if ((captureAudioDevice == deviceInfo) && (captureAudioFormat == null) && (DeviceInfo.formatToString(deviceFormat[y]).indexOf(defaultAudioFormatString) >= 0))
                    captureAudioFormat = (AudioFormat) deviceFormat[y];
                if (debug) System.out.println(" - format: " + DeviceInfo.formatToString(deviceFormat[y]));
            }
        }
        Format vformat = new VideoFormat(VideoFormat.H263, new Dimension(50, 50), Format.NOT_SPECIFIED, null, 15);
        Format aformat = new AudioFormat(AudioFormat.IMA4 /* LINEAR */);
        audioVideoOutputFormat[0] = vformat;
        audioVideoOutputFormat[1] = aformat;
        videoOutputFormat[0] = vformat;
        audioOutputFormat[0] = aformat;
        outputType = new FileTypeDescriptor(FileTypeDescriptor.QUICKTIME);
    }
 
    public void buildUI() {
        setLayout(new BorderLayout());
        Panel buttonPanel = new Panel();
        buttonPanel.setLayout(new FlowLayout());
        add("North", buttonPanel);
        startButton = new Button("Start");
        stopButton = new Button("Stop");
        startButton.addActionListener(this);
        buttonPanel.add(startButton);
        stopButton.addActionListener(this);
        buttonPanel.add(stopButton);
        buttonPanel.setVisible(true);
    }
 
    public synchronized String startVideoAudioCapture(String file) {
        DataSource finalDataSource = null;
 
        // setup video data source
        MediaLocator videoMediaLocator = captureVideoDevice.getLocator();
System.out.println("VIDEOMEDIALOCATOR === " + videoMediaLocator);
        DataSource videoDataSource = null;
 
        // setup audio data source
        MediaLocator audioMediaLocator = captureAudioDevice.getLocator();
        DataSource audioDataSource = null;
        try {
            videoDataSource = javax.media.Manager.createDataSource(videoMediaLocator);
System.out.println("VIDEODATASOURCE === " + videoDataSource);
            audioDataSource = javax.media.Manager.createDataSource(audioMediaLocator);
System.out.println("AUDIODATASOURCE === " + videoDataSource);
            DataSource dArray[] = new DataSource[2];
            dArray[0] = videoDataSource;
            dArray[1] = audioDataSource;
            finalDataSource = javax.media.Manager.createMergingDataSource(dArray);
System.out.println("FINALDATASOURCE === " + finalDataSource);
            ProcessorModel processorModel = new ProcessorModel(finalDataSource, audioVideoOutputFormat, outputType);
            processor = Manager.createRealizedProcessor(processorModel);
System.out.println("PROCESSOR === " + processor);
            // get the output of the processor
            DataSource source = processor.getDataOutput();
System.out.println("SOURCE === " + source);
            MediaLocator dest = new MediaLocator("file://" + file);
System.out.println("DEST == " + dest);
            // create a datasink to do the file
            filewriter = Manager.createDataSink(source, dest);
            filewriter.open();
            filewriter.start();
        } catch (Exception e) {
            e.printStackTrace();
        }
        try {
            processor.start();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }
 
//Stops the transmission if already started
    public void stop() {
        if (processor != null) {
            processor.stop();
            processor.close();
            processor = null;
        }
        if (filewriter != null) {
            try {
                filewriter.stop();
                filewriter.close();
                filewriter = null;
            } catch (IOException ioe) {
                ioe.printStackTrace();
            }
        }
    }
 
    public void run() {
        int i = 0;
        while (true) {
            while (continueCapture) {
                File f = new File(localDirectory, baseFileName + counter + ".mov");
System.out.println("FILE --- " + f.getAbsolutePath());           
                this.startVideoAudioCapture(f.getAbsolutePath());
System.out.println("Start transmission for " + baseFileName + counter + ".mov file for " + TIME_EACH_CLIP + " miliseconds...");
                try {
                    Thread.sleep(TIME_EACH_CLIP);
                } catch (InterruptedException ie) {
                    ie.printStackTrace();
                }
                this.stop();
System.out.println("...transmission ended for " + baseFileName + counter + ".mov");
                UploadThread ut = new UploadThread();
                ut.setFile(f.getAbsolutePath());
                ut.setuploadURL(uploadURL);
                ut.setName(baseFileName);
                ut.start();
                counter++;
            }
            try {
                Thread.sleep(TIME_EACH_CLIP);
            } catch (InterruptedException ie) {
                ie.printStackTrace();
            }
        }
    }
 
    public void start() {
        if (runThread == null) {
            runThread = new Thread(this);
        }
        runThread.start();
    }
 
    public void actionPerformed(ActionEvent event) {
        Button button = (Button) event.getSource();
        if (button == startButton) {
            continueCapture = true;
        }
        if (button == stopButton) {
            continueCapture = false;
        }
    }
}
 

I also enabled the option for allowing aplets to write to a file in the JMF Registry. But the exception still remains.

[Ulf Dittmer]

I created a policy file

Then it looks like you're not done with it yet :-)

I think the contents of the policy file matter more than the code of the applet; why don't you post what your have so far so we can take a look at it.

[Kedar Dravid]

Here's the content of my .java.policy file stored in my home folder:
grant { permission java.io.FilePermission "C:\\temp\\*", "read,write"; };
Also, to be doubly sure, I added the following lines to the default security policy file in <JAVA_HOME>/jre/lib/security.

[Ulf Dittmer]

Could it be that the JVM used by the browser is a different one than the one in JAVA_HOME? In that case it would have its own directories somewhere.