Applet Method Signed?

Hello,
I'm relativly new to the applet world so sorry if my question looks stupid.
I'm currently working on a Java applet that performs a screencapture and save it to the client file system.
To be able to capture the screen and write it , i had to sign the Applet.
It is what i did using : Keytool and Jarsigner tools.
So on my test applet , in the Init() method , i perform my screencapture and save it. It works well if the applet is signed , if not i have security exception that is normal.
Then i tried to move my code to another method. I removed it from the Init() and create a new method i named CaptureScreen() . And i copied my previous code in that method.
In my HTML Test page, i have embedded the applet using <APPLET> tag and add a HTML button that triggers a javascript that calls my method.
MyApplet.Capture();
My problem :
When i call this method on the signed applet i got a security exception.
java.security.AccessControlException: access denied (java.awt.AWTPermission createRobot)
If the same code is called in the Applet's Init'() method i don't have it.
So i guess i have to sign the Capture() method too. But how to do that? How to sign a specific method?
Thanks a lot in advance for your help
Youki

Hi
You don't sign methods. You sign the whole .jar file. So if you signed the file again after the adding the captureScreen() method, the applet .jar file should be OK.
Not sure but I guess the problem occurs because the calling script is not signed.
See http://java.sun.com/j2se/1.3/docs/guide/plugin/security.html
(I can't find the same information in newer plugin developer guides though.)

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I have a basic applet method timing problem with Firefox (and Chrome), not IE nor Opera. Works if JavaScript issues windows.alert() prior, fails otherwise.

I have an applet method, which is invoked from a JavaScript function, that is triggered by the window.onload event. The problem seems to center in the loading of the applet and its methods.
If I step through the 3 applet acceptance prompts (I chose to use a down-level Java), the applet method is never invoked, nor is an exception raised. How this happens is beyond my understanding.
As additional information, the Init(), start(), and "desired" Java methods all use the synchronized keyword. This is an attempt to minimize the exposure to a multi-thread environment.
If I issue a message from JavaScript (via window.alert()) PRIOR to invoking the method, I can get the desired results in special circumstances:
1) When the alert is presented, Firefox also prompts, SIMULTANEOUSLY, to block/continue the applet (the first of the 3 applet acceptance prompts). I can accept that these are separate threads.
2a) If I walk through the 3 applet acceptance prompts FIRST, and then hit the OK button on the alert message SECOND, I get the desired results, my applet method executes, and all is well (other than the fact that I would prefer not to have the alert in place at all).
2b) If I hit the OK button on the alert message FIRST, and then walk through the 3 applet acceptance prompts SECOND, I get the same results as when the page loads WITHOUT the alert, which is the applet method is never invoked, nor is an exception raised. Weird, huh?
The above problem only occurs when the browser and the applet's URL are loaded for the first time.
Subsequent invocations (after the page & applet has been loaded initially) do not have the failing symptoms.
It is my understanding that IE and Firefox (and Chrome and Opera, for that matter) each use the same implementation of JavaScript provided by Microsoft. Please correct me if this information is inaccurate.
The failing page and it's applet are proprietary; I cannot provide the Internet URL, nor the Java or JavaScript source, to aid in your analysis.

I can speak to the source code, but have no access to it.
The current process/thread that invokes an applet method must check to see that the applet is not currently being loaded by another process/thread. If it is being loaded, the current process/thread should block until the load is complete, THEN attempt to invoke the applet method.
Please forward my concern to a knowledgable developer. The nature of the problem, once identified, can be addressed in a very straightforward manner.

How to get the applet method value in javascript variable

Hi,
I have an applet which reading the text file content, text file has valued either ON or OFF
import java.applet.*;
import java.io.*;
public class A extends Applet
public String line="";
public void init( )
String strPath ="D:/WAS_Status.txt";
try
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                         line = objReader.readLine();
}catch( IOException e)
e.printStackTrace();
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<HEAD>
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Getting error as object doesnt support this property.
I tried, line=document.TestApplet.line;
Gets val as undefined.
The line variable of Applet will return either ON or OFF value.
Pls suggest where it has gone wrong or is there any other way?

Yes it is a reserved word to warn that this applet , lets say send messages to the HTML page that call it.
You will find the instruction how to do that at sun site.
Yes you have to implement an interface inside the applet (code)
and send a message to HTML with the name and parameters of
the Javascript you want to call!
But for all this to work you have to put in your project two new classes.
And after that call some methods that does the job you want.
Look for Java to JavaScript Comunication to get what you want!.
check this per exemple!
http://java.sun.com/products/plugin/1.2/docs/jsobject.html
See You ( Ate mais )

Java Applet Certificate Signing Window comes up BLANK!

Hi Everyone I have a problem where
Java Applet Certificate Signing Window comes up BLANK!
It comes up as blank gray panel with the java logo on the upper left.
the title bar says "Java Plugin Security Warning"
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I have tried clearing temp files deleting files from IE, deleting cookies, clearing the history.
Now i'm going to restart the computer and see if it works.
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Stephen

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2) bring up the plugin's console if it's not already and then go to a blank page.
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adina

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If I call applet method like :
function callbackFunc(){
var pp = appletID.getData();
alert(pp);
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Thanks

Hi Paul,
(1)Seems to be your Java Runtime Environment path is still setted for JRE 1.3.0_01 and not for 1.3.1. So pelase go to the
Control Panel-->java plugin 1.3.1-->Advanced. Here you set the Java Runtime Environment to the JRE 1.3.1 version. Its better to remove the older version before installing the new version on JRE.
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http://www.sun.com/developers/support

Problem calling applet method using IE

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public class test extends java.applet.Applet {
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<HTML>
<HEAD>
<script language="Javascript">
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<br>
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Craig Drabik
Sr. Programmer/Analyst
University at Buffalo

I have very similar problem, my applet works OK using Netscape (6.2 and 7.0), but with IE 6.0 It only works with windows XP;
The reported error is "Object doesn't support this property or method"
Can someone please help me to solve this problem.
Cheers
Horus
This is my code:
- I call the applet using javaScript and input the method setData with two strings.
function graphic()
     var dataZenith;
     var dataManual;
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     dataManual = graphicManual(); //Call other Javascript functions
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I run the applet with this HTML code:
<applet NAME="AppletOne" code="Appl.class" width="450" height="450"
MAYSCRIPT></applet>
//Applet code/////////////
import java.awt.*;
import java.awt.geom.*;
import java.applet.*;
import java.util.*;
public class Appl extends Applet {
     private int [] myArray1 = new int [156];
     private int [] myArray2 = new int [156];
     private boolean flag = false;
     // maxDataYAxesNumber es usado para dividir el eje de las Y
public void init()
          setFont(new Font("SansSerif", Font.BOLD, 12));
          setBackground (Color.white);
          setSize(getSize());
// Get data and put in an array
public void setData(String data1, String data2)
          final String DELIMITER = ",";
          final StringTokenizer theTokens1 =
               new StringTokenizer(data1, DELIMITER);
          final StringTokenizer theTokens2 =
               new StringTokenizer(data2, DELIMITER);
          try
                    String dataX = data1;
                    for (int i = 0; i < 156; i++)
                    myArray1[i] = Integer.parseInt(theTokens1.nextToken().trim());
                    myArray2[i] = Integer.parseInt(theTokens2.nextToken().trim());
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Graphics2D g2d = (Graphics2D)g;
setData(data1, data2) ;
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Problem accessing applet methods since 1.4.2_06

Hello,
I'm working with ie 6.0
I'm accessing applet methods from javascript
My applets were working fine until I installed the JRE 1.4.2_06 (I tested them with JRE 1.4.2_05 and it worked)
Now, when I call an applet method from javascript, I have a javascript exception, as if the applet is not loaded, but I think it is : I can see it in the traces in the java console !
I didn't modify the code, just the JRE.
It doesn't work with jre 1.5 too
Here a simple sample code that doesn't work with JRE 1.4.2_06 :
APPLET :
import java.applet.Applet;
public class Test extends Applet
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HTML :
<html>
<body>
<script language="JavaScript">
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</script>
<form name="myform">
<OBJECT NAME="test" WIDTH=500 HEIGHT=120 CLASSID="CLSID:8AD9C840-044E-11d1-B3E9-00805F499D93">
<PARAM NAME="code" value="Test.class">
<PARAM NAME="scripting" value="true">
</OBJECT>
     <input type="button" value="test !!" onclick="myTest()">
</form>
</body>
</html>
If you have any suggestion ...
Thanks

It should work, what if you try the following:
html file:
<html>
<body>
<script language="JavaScript">
function myTest() {
try{
     document.myform.test.test();
}catch(e){
     alert(e.description);
function myTest1() {
try{
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}catch(e){
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</script>
<form name="myform">
<OBJECT NAME="test" id="test" WIDTH=500 HEIGHT=120 CLASSID="CLSID:8AD9C840-044E-11d1-B3E9-00805F499D93">
<PARAM NAME="code" value="Test.class">
<PARAM NAME="scripting" value="true">
</OBJECT>
<input type="button" value="test !!" onclick="myTest()"><br>
<input type="button" value="test with getelementbyID!!" onclick="myTest1()"><br>
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</body>
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import java.applet.Applet;
public class Test extends Applet{
public void test() {
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public void init(){
     System.out.println("this is init");
When you open the page it should say "this is init" in the java console
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as the following format:
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Hi , i know that that is possible, i dont have the example right here just wait until tomorrow at the morning and i sent it to you , please send me a email to remaind me the code
[email protected]

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I am trying to invoke an applet method from javascript, but it is failing with Netscape 6 browser:
I am doing it the following way-
function test(form)
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Applet ignore sign

I have created an applet and signed it. Everything was greate until today. Suddenly when I try to sign new applets I get a message saying that the applet was signed, but when I execute it I see that it is not signed (I have checked that the expiration date hasn't passed yet).
I tried to create a new signature this way:
keytool -genkey -alias tkn8 -keystore tkn8 -validity 9000
Enter keystore password: q12345
What is your first and last name?
[Unknown]: Tkn8
What is the name of your organizational unit?
[Unknown]: Computers
What is the name of your organization?
[Unknown]: myOrg
What is the name of your City or Locality?
[Unknown]: Tv
What is the name of your State or Province?
[Unknown]: USA
What is the two-letter country code for this unit?
[Unknown]: US
Is <CN=Tkn8, OU=Computers, O=myOrg, L=Tv, ST=USA, C=US> correct?
[no]: yes
Enter key password for <tkina8>
(RETURN if same as keystore password):
I exported the signature
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Certificate stored in file <tkn8.crt>
I installed the certificate and signed the jar
jarsigner -keystore tkina8store TapiTkina.jar tkn8
But it doesn't work.
Can someone help me!!!

You can check your java.policy.
If there is something with "usePolicy" in there all signatures will be ignored for a certain codebase and you
won't get the popup. Note that if you have jre and jdk installed there are more than 1 policy files.
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i guess the problem is that you can't do anything in the applet outside the dialog if it is modal and visible.
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Hi,
It seems you are trying with proper format following things i can suggest.
Check date time format which you are passing should be correct.
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hope it helps!!
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Manoj Bilthare

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I have an embedded Applet in a web page, and I am trying to directly call a method in that Applet from the same page, using JavaScript.
Here is the complete Applet:
import java.applet.Applet;
public class Test extends Applet {
public String test() {
return "test() method return value";
}Here is the complete web page:
<HTML>
<HEAD><TITLE>Applet Invocation test</TITLE></HEAD>
<BODY>
<APPLET CODE="Test" WIDTH=10 HEIGHT=10 NAME="test"></APPLET>
<HR>
<SCRIPT>
document.write( "JavaScript is working<br>" );
document.write( document.test.test() );
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</BODY>
</HTML>Is there anything wrong with this? Because it works about 15% of the time, displaying an <HR>, "JavaScript is working", and then "test() method return value" on the next line.
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Thanks for the reply, I appreciate it. I have another question, if you don't mind... here is what my new test web page looks like:
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<HEAD>
<TITLE>Applet Invocation test</TITLE>
<SCRIPT>
function testFunc()
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<BODY onLoad="testFunc()">
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<HR>
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Applet Method Signed?

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