Display splash screen while downloading applet jar file

I've tried to search the forums, but most results I get are how to display a splash screen while the classes are loading. Unfortunately, the classes do not begin loading until after the jar file has been downloaded. How does one go about showing as splash screen as the jar file containing the classes is downloaded?
Thanks for the help!

"Java 5 provides a capability in this area"- Unfortunately, due to circumstances out of our control we are stuck on java 1.4.x.
"How you do that is your problem."- I'm so glad I can count on the helpful java community. Thanks.
Since it appears that "warnerja" is discusted by my question (mabye had a bad day) and is leaving me out in the cold, does anyone have any ideas on how I can implement her/his suggestion. I can break my jar file into multiple seperate jars and as each one loads I can update a progress bar. Unfortunately, I do not know where to begin with this code wise nor do I know if this is the best solution to this problem. I would think this to be a common problem.
Thanks for your help!

Similar Messages

Multiple repeat downloads of applet jar file

We have an applet that is downloaded from a Weblogic server. The applet is packaged as a jar file. Some of the testers have been complaining that the applet is extremely slow to start up.
The applet start-up involves three phases. In a first phase, it fetches data from the server. This phase seems to execute in pretty much constant time. During the second and third phases, it constructs a UI using Swing objects. The UI includes some JPEG files, which are extracted from the applet's own jar file.
Testers report that the slow part of start-up is actually the UI setup. This should theoretically not be network-bound at all. But packet tracing reveals that during this phase, there's a large amount of network traffic going on. It turns out that there are multiple GET requests for the applet jar file being issued. Typically, 29 requests are issued in all; just for reference, the applet is required to extract 28 images from its jar file, so it looks as if the additional requests correspond to image requests.
One further detail: this does not occur where there is a fast connection to the server. In these cases, the applet is downloaded once. It looks as if the problem only occurs on slower network connections, and the speculation here is that the applet jar is somehow being downloaded only partially, so that requests for images somehow trigger a re-request of the jar file.
Has anyone seen anything similar and, more to the point, is there a fix or workaround?
Technical details: Internet Explorer 5.5 or 6.0, JRE version 1.4.2_01 Java HotSpot(TM) Client VM (on the client), WebLogic 8.1 (on the server)
Thanks in advance for any help.

Ok.
I have been trying hard and found the solution. One of the ablove posting says that it works under java 1.4.1 plug-in. That's infact absolutely true. It also says that how to run client using JRE 1.4.2 or higher. That can be solved two. This is definitely a bug with the 1.4.2 plug-in.
Follow this procedure that will solve the mystry.
----------------------start ---------------------------------
Problem
Download of applet is very slow
Why?
This was happening because of the repeated download of the applet jars by the applet plug in controller. It is quite clear that the Java 1.4.2 plug in controller has a bug that causes the plug in to download same jar files multiple times irrespective of Jar cache in the client side (configurable from client side using the Java plug in control panel) is enabled or disabled. Therefore, we have moved from 1.4.2 plug in to 1.4.1 (controlled from our client (JSP) code) that works fine.
What the client (applet client) should do?
You must do the following in the client side in order to avoid the long download time for applet when running from a browser. We have also found that the browser actually do not matter in slow applet downloads. It is only the plug in that does control the applet download.
Irrespective of what JVM you have already installed (or not yet installed) please do the following:
1. Download the JRE 1.4.2 from http://java.sun.com/products/archive/index.html
-At the time of its installation if it shows that the "JRE is already installed do you uninstall it?" Go ahead and uninstall the JRE 1.4.2. After the un-installation again install the JRE 1.4.2
-If it does not have the JRE 1.4.2 already installed, then you will see any warning window and you will be able to install the 1.4.2 JRE successfully.
2. Now, go to the same link and install JRE 1.4.1.
-If this JRE already installed, uninstall first like the step 1 above. then reinstall it.
3. Now, after successful installation of the JRE 1.4.1, open the Plug-In control panel.
-You will find the list of control panel(s) in the Start->Control Panel window. Use the control panel that shows the version number 1.4.1. If no version number shown then use the one that do not show any version number at its end.
4. Do the following on the Plug-In control panel.
-Verify if this is the 1.4.1 plug in control panel? Go to the "About" tab to see if it shows 1.4.1.
If it does not show the 1.4.1 (or 1.4.1_x) then plug in was not installed correctly. Reinstall the 1.4.1 JRE following the step in no-2
-Go to "Basic" tab and select "Show console" radio button.
-Go to "Advanced" tab and from the drop down select "JRE ...1.4.2" from the "Java Runtime Environment" drop down box.
-Go to "Browser" tab and select all that in the "Settings" box applicable for browsers.
-Go to "Cache" select "Enable Caching" if it is not selected currently. Select "Unlimited" from "Size" options.
Now hit "Apply" button at the bottom and close the control panel using the 'X'.
5. Restart your Windows machine.
6. You are ready to run the applet from any of the browser (IE, NS, etc.)
--------------------------end------------------------------

How to load an applet jar file?

Hello everyone,
I have an applet that uses my own jar file and approximately 6 third party jar files. I set up jar indexing (jar -i) which will download the jar files when they are needed. All seems to work well, but now I want to manually load the jar files which I cannot get working.
When the applet starts, about 1/2 of the jar files are downloaded (because they are needed at startup). I then want to load the additional jar files in the background, after the gui is initialized. I have tried this using the below thread which is executed from within the applet's start method:
// Try to load additional jar files in background by loading a class from each jar file.
Thread loadClass = new Thread() {
public void run() {
    System.out.println("Loading classes...");
    try {
      // Tried loading classes this way, doesn't work.
      getClass().getClassLoader().loadClass("pkg1.Class1");
      getClass().getClassLoader().loadClass("pkg2.Class2");
      getClass().getClassLoader().loadClass("pkg3.Class4");
      getClass().getClassLoader().loadClass("pkg4.Class4");
      /* Loading classes this way doesn't work either.
      Class.forName("pkg1.Class1");
      Class.forName("pkg2.Class2");
      Class.forName("pkg3.Class3");
      Class.forName("pkg4.Class4");
    catch(ClassNotFoundException e) {
      // First attempt to load a class (pkg1.Class1) throws exception.
      System.out.println("Can't find class: " + e.getMessage());
loadClass.start();As you can see from above I am trying to load a class from each of the jar files so that the jar files would load into memory/cache. Unfortunately, it cannot find the classes. These are the errors from the java console:
Loading classes...
Loading: pkg1.Class1
Connecting http://my.server.com/my_dir/pkg1/Class1.class with no proxy
Connecting http://my.server.com/my_dir/pkg1/Class1.class with cookie "JSESSIONID=some_big_long_char_list"
Can't find class: pkg1.Class1
So it appears the jar file is not being downloaded. When I take away the dynamic jar loading (removing the "jar -i" & adding them all to the applet archive list) the thread executes correctly. So I know the class names, etc, are correct. How does one load an applet jar file?
Any help/suggestions are appreciated.

The above error I posted was because I forgot to index the jar files. That is why it couldn't find the jar file. I thought I was getting farther along with my problem, but I apparently just forgot to index the jars. I am now getting the problem that I got yesterday...
The applet freezes/hangs when it hits the thread. The GUI never opens (even though I'm running this thread right after the gui shows). The java console quits responding and the applet just stays the grey screen. I also tried the invoke later that you suggested.
public void start() {
// ...initialize gui...
// Applet freezes and remains grey, also the java console freezes.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
    public void run() {
      System.out.println("Loading classes...");
      try {
        // When I comment out the below forName calls, the thread will still run evidenced through the done print statement.
        Class.forName("pkg1.Class1");
     Class.forName("pkg2.Class2");
     Class.forName("pkg3.Class3");
     Class.forName("pkg4.Class4");
        System.out.println("...Done loading classes");
      catch(Exception e)     {
        System.out.println("Can't find class: " + e.getMessage());
}

Warning while downloading an Excel file from WD ABAP

Hi folks,
In one of requirements, Client wants to download all the data that is appearing on the screen ( WD ABAP Application ) to an Excel with a layout in different manner.
We achieved this with Simple Transformations.
Now the question is while downloading the excel file, the framework/other is throwing an Warning like
" The file you are trying to open, 'info.xls', is in a different format than specified by the extension. Verify that the file is not corrupted and is from a trusted source before opening the file. Do you want to open the file now? "
Note: All the users of my client are using MS Office 2002 / 2003.
I am using the following code........!
*------ Call Transformation for Excel OUTPUT
CALL TRANSFORMATION ZEXCEL_OUTPUT
      SOURCE
             t_dates     = t_dates
             t_info        = t_info
      RESULT XML l_xml_string.
REPLACE ALL OCCURRENCES OF '<?xml version="1.0" encoding="utf-16"?>' l_xml_string WITH '<?xml version="1.0"?><?mso-application progid="Excel.Sheet"?>'.
**-- Call Function Module for converting string data to XSTRING
CALL FUNCTION 'SCMS_STRING_TO_XSTRING'
    EXPORTING
      text           = l_xml_string
      mimetype = 'application/xml'
    IMPORTING
      buffer      = l_xml_xstring
    EXCEPTIONS
      failed   = 1
      OTHERS   = 2.
CALL METHOD cl_wd_runtime_services=>attach_file_to_response
    EXPORTING
      i_filename       = 'info.xml'
      i_content        = l_xml_xstring
      i_mime_type   = 'application/vnd.ms-excel'.
With this code I am generating a file of type XML SPREADSHEET 2003. While opening this file I am getting the above message which the user unwanted......
Can any one help me on this -
> How to avoid this warning?
Thanks and Regards,
Aneel Danda
Edited by: danda aneel on Jul 13, 2010 1:43 PM

Firstly, Thanks for Your quick Response, Thomas.
Even though what ever may be the file name I am passing either info.xml or Info.xls , In error info.xls is coming.
Kindly provide me an alternative on this XML doesn't seem like it would match the 'application/vnd.ms-excel'.
what is the supported format.?
Similarly, It is not considering the UTF-8 / UTF-16 for xml.........same result is appearing in the output.
Edited by: danda aneel on Jul 14, 2010 7:52 AM

Where is the Applet JAR file?

When an Applet (the JAR) is downloaded to the local PC, exactly where (the directory) we can locate the Applet JAR file? Is the file managed by the Internet browser?

This has got to be browser-specific.
You shouldn't write code that depends on this kind of information anyway.

Problem when downloading the JAR file

I'm just install JRE and testing my first applet application. I'm facing the problem that I can not download the JAR file from my localhost computer.
I've enable cache in Java Control Panel and running my applet. Normally, it will download the jar file from my localhost and save it to the cache directory of Java. And then finding all classes neccessary to run my applet in the JAR file.
But I discover that I can not download the JAR file and save to my computer. I try to put the URL to download this JAR file (http://localhost/myjar.jar) in my web address, it start to download this file properly. But when open it with WINRAR, I got an error that the file "Unexpected end of file".
I try to put this file from onther computer in my LAN. And use the URL to download it. This time I can open the JAR file with WINRAR althrought the file size is the same
Anyone know why there are some errors when download from my localhost? Thanks in advance for any help!!!

Yeah everything matches up!
Could it have something to do with the string encoding? I created the file in ANSI format? Would this have an effect on it?

While executing a jar file I am getting an error

while exec a jar file i am getting an error
invalid file (bad magic number): Exec format error
i tried to execute it with the commnad
java -jar test.jar
or by directly too
./test.jar

Than tell me how to launch a jar file I tried different ways like
java -jar MyJar.jar
and
MyJar
and
./MyJar
but its not worked

Downloading a jar file

Hi guys,
i want to download a jar file from an url: www.xxx.com/file.jar
now how is the best way todo this?
Thanks in advance!

Since I saw the post before you edited it, I'm going to assume that you accidentally provided a URL that linked to a sex site. Therefore I shall just block the post.

Question about Java Applet Jar file signing.

These questions pertain to Java 6 Standard Edition 1.6.0_22-b04 and later.
I have gone through the Oracle Java Tutorial for generate public and private key information
to sign a jar file, and how to sign the jar itself, all at
[http://java.sun.com/developer/onlineTraining/Programming/JDCBook/signed.html|http://java.sun.com/developer/onlineTraining/Programming/JDCBook/signed.html]
, and seek some clarification on the following related questions:
-In order to "escape" the java applet sandbox that exists around the client's
copy of the applet running in their web browser, ie.
(something forbidden by default), is verification of the signed applet enough, or is a policy file required
to stipulate these details?
-using the policytool policy file generator, what do I need to add under "Principals"
(if anything) when dealing with a Java applet? Are Codebase and SignedBy simply author information?
-If I choose to use a java.security.Permission subclass object set up in equivalent fashion within the Applet,
which class within the Applet jar do I instantiate that object in? Does it need to be mentioned
in the applet's jar Manifest.MF file?
-Is the "keystore database" a java language service/process which runs in
the Server's memory and is simply accessed and started by default
by the client verifier program (appletview/web browser)?
-The public key certificate file (*.cer) is put in the webserver directory holding
the Applet jar file (ie. Apache Tomcat, for example).
-Presumably, the web browser detects the signed jar
and certificate file, and provides the browser pop up menu asking the user
about a new, non recognised certificate (initially).
Is this so?
-With this being the case, can the applet now escape
the sandbox, be it with or without the stipulated
policy permissions?

848439 wrote:
-In order to "escape" the java applet sandbox that exists around the client's
copy of the applet running in their web browser, ie.
(something forbidden by default), is verification of the signed applet enough, or is a policy file required
to stipulate these details?Just sign the applet, the policy file is not necessary.
-Is the "keystore database" a java language service/process which runs in
the Server's memory and is simply accessed and started by default
by the client verifier program (appletview/web browser)?No.
-The public key certificate file (*.cer) is put in the webserver directory holding
the Applet jar file (ie. Apache Tomcat, for example).No. For a signed Jar, all the information is contained inside the Jar.
-Presumably, the web browser detects the signed jar
and certificate file, and provides the browser pop up menu asking the user
about a new, non recognised certificate (initially).
Is this so?No. It is the JVM that determines when to pop the confirmation dialog.
-With this being the case, can the applet now escape
the sandbox, ..Assuming the end-user OK's the trust prompt, yes.
..be it with or without the stipulated
policy permissions?Huh?

Exception is thrown only while executing the jar file

java.lang.NoClassDefFoundError: javax/mail/Address Exception is thrown only while executing the jar file. But the program compiles and executes good when executed for command prompt through the class files.
I used javamail API in my program. Classpath and every others are set to the right one's. Executed fine when used java Random.class. But the problem is only with the jar file.
Please help me out in this regard. Why the exception is thrown only in jar but not at class level.

Assuming you're running your program using "java -jar", your jar file needs a Class-Path entry
in the manifest file that references mail.jar.

How to download the .jar files for ESB?

Hi,
I'm connecting to a remote sandbox environment of CE 7.2. I'm running into the problem that some links point to URLs without a fully qualified host name. For example, in ESR (url .../rep) the link that points to the Enterprise Service Builder is http://server:port/rep/start/repository.jnlp instead of http://server.company.com:port/rep/start/repository.jnlp
As a result, clicking the link results in Page not found.
As a workaround, I can type the URL manually in the address field of my browser.
That way, I can launch Web Start. However, it does not solve my problem, because soon after, the download fails because some of the .jar files have the short URL.
I get the error message "Unable to load resource: http://host:port/rep/repository/com.sap.xpi.ibrep.client.jar
Now how can I download the .jar files so that I can start the ESB? Typing the URL into the browser doesn't seem to work, and I don't know what else I should download to launch ESB.
Is there a post-installation way to specify the URL for the components?
Edited by: Arto Pihlaja on Dec 4, 2010 11:37 PM

Found it.
I had to change the value of the parameter com.sap.aii.connect.repository.name under CE - Administration - Properties Administration.

To display splash screen for certian period of time using threads

i want to write a program to display splash screen for certian period of time using threads. could some one help me

If you just want a splash screen: [http://java.sun.com/developer/technicalArticles/J2SE/Desktop/javase6/splashscreen/|http://java.sun.com/developer/technicalArticles/J2SE/Desktop/javase6/splashscreen/]
If you want to learn threads: [http://java.sun.com/docs/books/tutorial/essential/concurrency/|http://java.sun.com/docs/books/tutorial/essential/concurrency/]

My Applet Jar file doesn't work !!

hello ,
I have written this java applet :
import java.awt.*;
import javax.swing.*;
import java.applet.Applet;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.URL;
public class test4 extends Applet implements ActionListener{
     private static final long serialVersionUID = 1L;
     private JButton B1 =new JButton("Forward ");
     private JButton B2 =new JButton("Backward");
     private JButton B3 =new JButton("Left");
     private JButton B4 =new JButton("Right");
private JPanel P1 = new JPanel();
private JPanel P2 = new JPanel();
private JPanel P3 = new JPanel();
private JPanel P4 = new JPanel();
private JPanel P5 = new JPanel();
private JPanel P6 = new JPanel();
private JLabel L3 = new JLabel(" ");
private JLabel L4 = new JLabel(" ");
private JLabel L5 = new JLabel(" ");
private JLabel L6 = new JLabel(" ");
private JLabel L7 = new JLabel(" ");
JSplitPane sppSplitPane0 = new JSplitPane( );
     public test4()
          JFrame.setDefaultLookAndFeelDecorated(true);
          sppSplitPane0.setDividerLocation( 250 );
          P3.add(L4);
          P3.add(B1);
          P3.add(L5);
          P5.add(B3);
          P5.add(L3);
          P5.add(B4);
          P4.add(L6);
          P4.add(B2);
P4.add(L7);
          P1.setLayout(new BorderLayout());
          P1.add("North",P3);
          P1.add("Center",P5);
          P1.add("South",P4);
          P2.setLayout(new BorderLayout());
          P2.add("North" , P1);
          B1.addActionListener(this);
          B2.addActionListener(this);
          B3.addActionListener(this);
          B4.addActionListener(this);
          sppSplitPane0.setLeftComponent(P2);
          sppSplitPane0.setRightComponent(P6);
     public void actionPerformed(ActionEvent e) {
          try {
               if (e.getSource() == B4) {
          URL myNewURL = new URL("http://amera/cgi-bin/test.cgi?R");
          System.out.println("URL = " + myNewURL);
          getAppletContext().showDocument(myNewURL,"blank");
               else
                    if (e.getSource() == B3) {
                    URL myNewURL = new URL("http://amera/cgi-bin/test.cgi?L");
                    System.out.println("URL = " + myNewURL);
                    getAppletContext().showDocument(myNewURL,"blank");
                    else
                         if (e.getSource() == B2) {
                         URL myNewURL = new URL("http://amera/cgi-bin/test.cgi?B");
                         System.out.println("URL = " + myNewURL);
                         getAppletContext().showDocument(myNewURL,"blank");
                         else {
                              URL myNewURL = new URL("http://amera/cgi-bin/test.cgi?F");
                              System.out.println("URL = " + myNewURL);
                         getAppletContext().showDocument(myNewURL,"blank");
          } catch (Exception err) {
          System.err.println("Error!\n" + err);
          showStatus("Error, look in Java Console for details!");
     public static void main(String[] args) {
          test t=new test();
          JFrame frame =new JFrame();
          frame.add(t.sppSplitPane0);
          frame.setSize(1100,700);
          frame.setVisible(true);
i made a jar file :
i created a file and named it MANIFEST.MF .i wrote inside it :
Main-Class: test
Then i placed it in a folder with the test.class .I created jar file using command line.
I entered the test.class path and then wrote this command :
jar cvfm myjar.jar MANIFEST.MF *.class
Then the jar file "myjar.jar" is created .
it's executed but this function "public void actionPerformed(ActionEvent e) " won't wrok.
i keep pressing the buttons but nothing is happening !!
please help me .
Edited by: Amera on Dec 27, 2009 2:51 PM

Welcome to the Sun forums.
Subject: My Applet Jar file doesn't work !! .
1) Note that one '!' denotes exclamation, whereas 2 or more often denotes a dweeb.
2) Since you are on your first post, I will point out that applets are an advanced topic, and should not be attempted by newbies.
3) "doesn't work" is very vague. It is likely to produce a reply like "maybe the applet is lazy - try flogging it".
Amera wrote:
..I have written this java applet :When posting code, code snippets, HTML/XML or input/output, please use the code tags. The code tags help retain the formatting and indentation of the sample. To use the code tags, select the sample and click the CODE button.
Also note that the most preferred form of code is an SSCCE *(<- link).* In an SSCCE, your would remove all but one button (if the actionPerformed fails with 6 or 7 buttons, trim it down to fail with just one or two.
i made a jar file :So does the applet work before you make the Jar file? Your post so far suggests the Jar file is the problem.
i created a file and named it MANIFEST.MF .i wrote inside it :
Main-Class: test
Then i placed it in a folder with the test.class .I created jar file using command line.
I entered the test.class path and then wrote this command :
jar cvfm myjar.jar MANIFEST.MF *.class
Then the jar file "myjar.jar" is created .
it's executed but this function "public void actionPerformed(ActionEvent e) " won't wrok.
i keep pressing the buttons but nothing is happening !!So you get 'no output in the console & no effect in the applet'?
What is the URL where I can see your applet failing?
As an aside, since Sun does not guarantee that applet clients will act on the showDocument command, even if it does not work, it would not be a 'bug'.
Edited by: AndrewThompson64 on Dec 28, 2009 11:18 AM

From where can I download the jar files to use JAXB 2.0?

Hi all,
From where can I download the jar files to use JAXB 2.0?
~Regards

Does the government not let you do Internet searches where you live? My Internet search for "JAXB 2.0" returned this:
https://jaxb.dev.java.net/
as the first link. If you can't find it from that page it doesn't exist.

Cipher.getInstance closes Applet JAR file.

I am trying to use a Cipher in a signed Applet in java plugin-1.4 under I.E. Once I execute a Cipher.getInstance the applet jar file is closed and I cannot create any new classes that havent been previously loaded from it. The classloader ends up returning an "IlleagleStateException: Zip file closed".
Is this a known bug? Is there a workaround? Perhaps a way to re-open the JAR file.
I have been combing the FAQ's without finding any other refrences to the problem.

I haven't found a solution to the original problem but for someone else that is looking for a workaround for this. I found that if I use two JAR with my Cipher in the second one, I can still load class files out of the first. I.E. <PARAM NAME = java_archive VALUE = "supportClasses.jar,mainApplet.jar"> where mainApplet.jar contains the code that uses the Cipher.

Display splash screen while downloading applet jar file

Similar Messages

Maybe you are looking for