Help with applet error

[4345487]

Hi,

I'm trying to call a applet from a html page an get an error

Code:

public void refreshResults( String sourceSelect, String sourceValue, String destSelect, String cgiName ) throws Exception
{

String uri = cgiName + "?source=" + sourceSelect + "&dest=" + destSelect + "&value=" + sourceValue ;
values = new Vector();
descs = new Vector();

java.net.URL url = new java.net.URL( uri );
java.net.URLConnection urlCon = url.openConnection();
ObjectInputStream in = new ObjectInputStream(urlCon.getInputStream());

values = (Vector) in.readObject();
descs = (Vector) in.readObject();

in.close();
}


but I get this error:

java.io.StreamCorruptedException: InputStream does not contain a serialized object

Thanks

 

[sedj]

This line :

ObjectInputStream in = new ObjectInputStream(urlCon.getInputStream());

attempts to create a java object from the the stream - but it is not a serialized java object. What are you expecting it to be and why are you using ObjectInputStream ?

--------------------------------------------------
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[4345487]

Hi,

Thanks for aswering the question:

I'm new to Java and looking for a way to do remote scripting and that code is a sample that I find. I'm a ASP developer and I use Microsoft remote scripting before where I would have a combo box pick something and with out refreshing the page I could fill up another list box and I try to do that with java.

 

[sedj]

So you actually do want to serialize an object on the server and deserialize it on the client ? How are you serializing the desired object ?

--------------------------------------------------
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http://www.primrose.org.uk

 

[4345487]

Yes that is what I want to do but how.

Thanks

 

[sedj]

Well, I think you will have major problems if you serialize Swing/AWT components on a server and then serialize them, send the object to the client, and then deserialize it at the client.

But if you really want to try, then read this tutorial :

http://java.sun.com/docs/books/tutorial/essential/io/serialization.html

--------------------------------------------------
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[4345487]

Thank you. Do you have any recommendations.

 

[sedj]

Just use Swing/AWT in the applet as normal ... I'm not entirely sure what you are trying to do ...

--------------------------------------------------
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[4345487]

I will try that.

This is what I'm trying to do lets said I have an form in that form I have a combo box with countries when I user selects the USA I want with out refreshing the form update a state list box with all of the states and if the choose Canada update the same list box with all the province.

 

[sedj]

But if you are usinf Applets, then there is no "form submission" - the applet is running on the client - you are not submitting a web page to the server - its all running on the client machine, so you can maipulate the graphics device as required. Are you completelt understanding what exactly an applet is ? In MS terms, its similar to an ActiveX control - it has no explicit ineraction with the server really apart from loading the code into the client browser...

--------------------------------------------------
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http://www.primrose.org.uk