How to unload a class or a dll from jvm?

We can load a class or a dll into jvm,but how can we unload a class or a dll from jvm?
I'm look forward to your reply.
Regard!
Sun.Huang

i don't believe you can unload a class.A class can only be unloaded if its classloader
becomes unreachable, so classes loaded by the
bootstrap loader will never be unloaded.Are they definately unloaded in that case? as soonas
the classloader that loaded them is unreachable?or
is it still an optional decision for the jvm?A class may be unloaded if and only if its defining
classloader may be reclaimed by the garbage
collector. There are no guarantees that a class will
be unloaded.Okay, that's what I thought. Thanks for confirming.

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Message Edited by Richard Ballantyne on 07-25-2007 02:39 PM
Message Edited by Richard Ballantyne on 07-25-2007 02:39 PM
Attachments:
binary_file_to_ascii.zip ‏192 KB

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How to convert java class to dll file for using in Microsoft Technology(.n)

hey hemmj !!!!!!
nice replying , first of all i d like to say thanks for response me so frequently..... i like such type of guy... i d never forget ur online support.
hey buddy, i ve a problem with applet application...
i m working on java chat server build on swing applet. As it is chat server, it is divided into two parts, one is server application and other is client application. I want to run this server app on the client server and the basic thing with this site is that it is running on .net platform(Microsoft). and the other app ll running on the client machine or end user. Now the problem is that this site would run only if the server app ll be run on server. This server app ll open the socket of server, which ll listen the request of the user...... So, the requirement is to convert this java sever class file into dll file and register this dll file with the IIS server.So, It run and stop with the IIS server.
I ve already search the way to convert the java class file into dll file. This is possible in such way........... below code is for the java class file...
import java.net.*;
import java.io.*;
import java.util.*;
public class chatServer
public static void main(String args[]) throws Exception
ServerSocket sersoc=new ServerSocket(1234);// Any port number above 1000 should do
// as most ports below 1000 are used by system
Vector socvec=new Vector();
String data="";int i,j=0;
BufferedReader in;
//System.out.println("Listening of port " + sersoc.getLocalPort());
//System.out.println("Waiting for connections...");
while(true)
Socket soc=sersoc.accept();
socvec.addElement(soc);
chatServerReadThread csrt=new chatServerReadThread(socvec, soc);
in=new BufferedReader(new InputStreamReader(soc.getInputStream()));
PrintStream out=new PrintStream(soc.getOutputStream());
out.println("Connected to chat server");
out.flush();
data= in.readLine();
for(i=0;i<socvec.size();i++)
soc=(Socket)socvec.elementAt(i);
out=new PrintStream(soc.getOutputStream());
out.println(data + " connected");
out.flush();
//System.out.println(data + " connected");
csrt.start(); // error is comming from here..... plz help me.
class chatServerReadThread extends Thread
Vector socvec;
PrintStream out;
chatServerReadThread(Vector socvec, Socket soc)
this.socvec=socvec;
try
out=new PrintStream(soc.getOutputStream());
}catch(Exception e){}
public void run()
try
String data;
Socket soc;
BufferedReader in;
while(true)
for(int i=0;i<socvec.size();i++)
soc=(Socket)socvec.elementAt(i);
in=new BufferedReader(new InputStreamReader(soc.getInputStream()));
if(in.ready())
try
data=in.readLine();
if(data.charAt(0) == ']')
data = in.readLine() + " exited";
//System.out.println(data);
socvec.removeElement(soc);
for(int e=0;e<socvec.size();e++)
soc=(Socket)socvec.elementAt(e);
out=new PrintStream(soc.getOutputStream());
out.println(data);
out.flush();
else
for(int e=0;e<socvec.size();e++)
soc=(Socket)socvec.elementAt(e);
out=new PrintStream(soc.getOutputStream());
out.println(data);
out.flush();
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}catch(Exception e){e.printStackTrace();}
first i ve made the jar file of this class
jar cvf chatServer.jar chatServer.classafter getting the jar chatServer.jar. I ve opened the .net dos prompt and
type this command which ll make dll file automatically....
> jbimp /t:library chatServer.jar
And you'll see the following output:
Microsoft (R) Java-language bytecode to MSIL converter version 1.1.4322.0
for Microsoft (R) .NET Framework version 1.1.4322
Copyright (C) Microsoft Corp 2000-2002. All rights reserved.
Created chatServer.dll
I cant get the problem origin from where it is comming, when i tried to convert it into .dll file it shown an error that, it did not recongnized the method in first class
public static void chatServerReadThread.start() method
is not recognized by .net dos prompt commnad. But when i omit this method it gets created the .dll file. This start method is basically the default method of thread class that run the thread from the same class..
By vewing the code u can visulize the thing,, i ve marked the code from where the error is comming.
Plz do it as soon as possible, i ll waiting for ur reply......
I ll be really thanking u for that....
Thanx and regards
Niraj Kumar Singh

I wonder if this will work:
jbimp /t:exe chatServer.jar
Your chatServer is an application that can be started from the commandline.
A dll is a library to be used in com, com+, other executables or ....

How to convert .class file to .dll file

hi,
I got a problem, I have to convert my java .class file to .dll file. Microsoft VC++ program will invoke the converted .dll file.
Is there any other possibility.
I was confused.
Cam any body help me. If you are having solution for the can you send to my [email protected] account.
thanks,

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