Running multiple java-apps in single JVM?

We have about 125 Citrix clients running on 5 Citrix Servers. We are investigating a new very big development project which will cover about 10 main projects with 15 Applications each. The complete project will be written in Java.
Basically, each module will have it's own JVM. BUt, when each client runs a couple of modules, the servers will surely run out of memory...
I searched for way's to run different modules within 1 single JVM but it seems to be 'not done', because of 'System.exit()', 'Static Variable' probs to name only 2.
Any idea's on how to implement this?
thanks.

thanks for the reply.
Yes, I assume the server will run out of memory.
1) Our citrix servers are consuming about 3/4th of their 4Gb memory capacity without any java_application running.
2) Each of our 5 Citrix servers has 25 users active
3) Each JVM takes about 20mb memory
4) Each user will run at least 3 app's simultaneously
Abouve results in 3*20=60Mb / user * 25= 1,5Gb memory extra needed.
Can you give me an example of a Thread.sleep(60000) test_pgm?
and/or an example for a "classloader" program to launch each app in its ow sandbox (in same JVM)?
(eventually a link to get more info on this)
thanks

Similar Messages

How do I run multiple java apps in one JVM to reduce memory use?

Hi all,
I saw an article either on the web or in a magazine not too long ago about how to "detect" if the app is already running, and if so, it hands off the new instance to the already running JVM, which then creates a thread to run the Java app in. As it turns out, my app will be used in an ASP environment, through Citrix. We may have as many as 50 to 100 users running the same app, each with their own unique user ID, but all using the same one server to run it on. Each instance eats up 25MB of memory right now. So the question is if anybody knows of a URL or an app like this that can handle the process of running the same (or even different Java) apps in one JVM as separate threads, instead of requring several instances of the JVM to run? I know this article presented a fully working example, and I believe I know enough to do it but I wanted ot use the article as a reference to make sure it is done right. I know that each app basically would use the same one "launcher" program that would on first launch "listen" to a port, as well as send a message through the port to see if an existing launcher was running. If it does, it hands off the Java app to be run to the existing luancher application and shuts down the 2nd launching app. By using this method, the JVM eats up its normal memory, but each Java app only consumes its necessary memory as well and doesn't use up more JVM instance memory.
Thanks.

<pre>
import java.util.Properties;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
import java.util.Enumeration;
import java.util.NoSuchElementException;
public class RunProg implements Runnable, Cloneable
private String iProg;
private String iArgs[];
public static void main(String args[])
new RunProg().main();
// first step is to start main program itself
private void main()
Properties properties = System.getProperties();
try
properties.load(new FileInputStream("RunProg.properties"));
catch(IOException e)
System.setProperties(properties);
int i = 0;
System.out.println("enter main, activeCount=" + Thread.activeCount());
while(true)
String program = properties.getProperty("Prog" + i);
if(program == null)
break;
StringTokenizer st = new StringTokenizer(program);
String[] args = new String[st.countTokens() - 1];
try
RunProg rp = (RunProg)this.clone();
rp.iProg = st.nextToken();
for(int j = 0; st.hasMoreTokens(); j++)
     args[j] = st.nextToken();
rp.iArgs = args;
Thread th = new Thread(rp);
th.setName("prog" + i + "=" + program);
th.start();
System.out.println("prog" + i + "=" + program + ", started");
catch(CloneNotSupportedException e)
System.out.println("prog" + i + "=" + program + ", can't start");
i++;
     System.out.println("end of main, activeCount=" + Thread.activeCount());
// next step is to start all others one by one
public void run()
try
Class c = Class.forName(iProg);
Class p[] = new Class[1];
p[0] = String[].class;
Method m = c.getMethod("main", p);
Object o[] = new Object[1];
o[0] = iArgs;
m.invoke(null, o);
catch(ClassNotFoundException e)
System.out.println(iProg + "ClassNotFoundException");
catch(NoSuchMethodException e)
System.out.println(iProg + "NoSuchMethodException");
catch(InvocationTargetException e)
System.out.println(iProg + "NoSuchMethodException");
catch(IllegalAccessException e)
System.out.println(iProg + "NoSuchMethodException");
System.out.println(Thread.currentThread().getName() + ", ended");
System.out.println("exit run, activeCount=" + Thread.activeCount());
// setup SecurityManager to disable method System.exit()
public RunProg()
     SecurityManager sm = new mySecurityManager();
     System.setSecurityManager(sm);
// inner-class to disable method System.exit()
protected class mySecurityManager extends SecurityManager
     public void checkExit(int status)
          super.checkExit(status);
          Thread.currentThread().stop();
          throw new SecurityException();
* inner-class to analyze StringTokenizer. This class is enhanced to check double Quotation marks
protected class StringTokenizer implements Enumeration
private int currentPosition;
private int maxPosition;
private String str;
private String delimiters;
private boolean retTokens;
* Constructs a string tokenizer for the specified string. All
* characters in the <code>delim</code> argument are the delimiters
* for separating tokens.
* <p>
* If the <code>returnTokens</code> flag is <code>true</code>, then
* the delimiter characters are also returned as tokens. Each
* delimiter is returned as a string of length one. If the flag is
* <code>false</code>, the delimiter characters are skipped and only
* serve as separators between tokens.
* @param str a string to be parsed.
* @param delim the delimiters.
* @param returnTokens flag indicating whether to return the delimiters
* as tokens.
public StringTokenizer(String str, String delim, boolean returnTokens)
currentPosition = 0;
this.str = str;
maxPosition = str.length();
delimiters = delim;
retTokens = returnTokens;
* Constructs a string tokenizer for the specified string. The
* characters in the <code>delim</code> argument are the delimiters
* for separating tokens. Delimiter characters themselves will not
* be treated as tokens.
* @param str a string to be parsed.
* @param delim the delimiters.
public StringTokenizer(String str, String delim)
this(str, delim, false);
* Constructs a string tokenizer for the specified string. The
* tokenizer uses the default delimiter set, which is
* <code>"\t\n\r\f"</code>: the space character, the tab
* character, the newline character, the carriage-return character,
* and the form-feed character. Delimiter characters themselves will
* not be treated as tokens.
* @param str a string to be parsed.
public StringTokenizer(String str)
this(str, " \t\n\r\f", false);
* Skips delimiters.
protected void skipDelimiters()
while(!retTokens &&
(currentPosition < maxPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) >= 0))
currentPosition++;
* Tests if there are more tokens available from this tokenizer's string.
* If this method returns <tt>true</tt>, then a subsequent call to
* <tt>nextToken</tt> with no argument will successfully return a token.
* @return <code>true</code> if and only if there is at least one token
* in the string after the current position; <code>false</code>
* otherwise.
public boolean hasMoreTokens()
skipDelimiters();
return(currentPosition < maxPosition);
* Returns the next token from this string tokenizer.
* @return the next token from this string tokenizer.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
public String nextToken()
skipDelimiters();
if(currentPosition >= maxPosition)
throw new NoSuchElementException();
int start = currentPosition;
boolean inQuotation = false;
while((currentPosition < maxPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) < 0 || inQuotation))
if(str.charAt(currentPosition) == '"')
inQuotation = !inQuotation;
currentPosition++;
if(retTokens && (start == currentPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) >= 0))
currentPosition++;
String s = str.substring(start, currentPosition);
if(s.charAt(0) == '"')
s = s.substring(1);
if(s.charAt(s.length() - 1) == '"')
s = s.substring(0, s.length() - 1);
return s;
* Returns the next token in this string tokenizer's string. First,
* the set of characters considered to be delimiters by this
* <tt>StringTokenizer</tt> object is changed to be the characters in
* the string <tt>delim</tt>. Then the next token in the string
* after the current position is returned. The current position is
* advanced beyond the recognized token. The new delimiter set
* remains the default after this call.
* @param delim the new delimiters.
* @return the next token, after switching to the new delimiter set.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
public String nextToken(String delim)
delimiters = delim;
return nextToken();
* Returns the same value as the <code>hasMoreTokens</code>
* method. It exists so that this class can implement the
* <code>Enumeration</code> interface.
* @return <code>true</code> if there are more tokens;
* <code>false</code> otherwise.
* @see java.util.Enumeration
* @see java.util.StringTokenizer#hasMoreTokens()
public boolean hasMoreElements()
return hasMoreTokens();
* Returns the same value as the <code>nextToken</code> method,
* except that its declared return value is <code>Object</code> rather than
* <code>String</code>. It exists so that this class can implement the
* <code>Enumeration</code> interface.
* @return the next token in the string.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
* @see java.util.Enumeration
* @see java.util.StringTokenizer#nextToken()
public Object nextElement()
return nextToken();
* Calculates the number of times that this tokenizer's
* <code>nextToken</code> method can be called before it generates an
* exception. The current position is not advanced.
* @return the number of tokens remaining in the string using the current
* delimiter set.
* @see java.util.StringTokenizer#nextToken()
public int countTokens()
int count = 0;
int currpos = currentPosition;
while(currpos < maxPosition)
* This is just skipDelimiters(); but it does not affect
* currentPosition.
while(!retTokens &&
(currpos < maxPosition) &&
(delimiters.indexOf(str.charAt(currpos)) >= 0))
currpos++;
if(currpos >= maxPosition)
break;
int start = currpos;
boolean inQuotation = false;
while((currpos < maxPosition) &&
(delimiters.indexOf(str.charAt(currpos)) < 0 || inQuotation))
if(str.charAt(currpos) == '"')
inQuotation = !inQuotation;
currpos++;
if(retTokens && (start == currpos) &&
(delimiters.indexOf(str.charAt(currpos)) >= 0))
currpos++;
count++;
return count;
</pre>
RunProg.properties like this:
Prog1=GetEnv 47838 837489 892374 839274
Prog0=GetEnv "djkfds dfkljsd" dsklfj

Running 2 java apps means 2 JVM instances ?

For each running Java application I start on my desktop do I get a seperate instance of the JVM ? If so that seems like such a waste ...

Yes. If you find this wasteful, though, you could write a Java application that runs your applications in a single JVM, in separate threads, but that would be violating the first two rules of optimization:
1. Don't do it.
2. Don't do it yet.
Those rules are there to remind you not to try to optimize a situation until you know that it needs to be optimized and until you know how to optimize it.

Running multiple java apps simultaneously, each using a different jre.

I have a situation where I have 3 or 4 applications (and one applet) that were built over time, each with a different version of the jdk (ranging from 1.2.2.005 to 1.3.2). I need to know of a way (and it must exist) to run each of these applications on the same machine, and at runtime, have each application (or applet) run with its respective version of the jre. Certainly, one could change some source code and make all programs compatible with a particular jre, but that doesn't solve my problem if a new app is built with a new version of the jdk down the road. Currently, each runs fine by themselves, but if I try to run them together as different processes, some won't do anything because the default jre may not be what it needs. Would the Java Plug-in software have a role to play in this? Is there a way to specify (link) which application should use which jre?
P.S. These applications (right now) don't have to interact or interface in any way. I just need to have them all running as separate processes on the same machine and be able to jump from one to the other.

However ... if you have the programs running in Java1.x, I
wouldn't recommend to let it run under Java 1.y; atleast
not without thorough testing.I do it all the time and have not had a problem. I'm
currently using JDK 1.4 beta 3 and I regularly run a
Java application written with JDK 1.1.
It sounds like the programs you are running are
relying on behavior that is not guaranteed. If that
behavior changes in a later version, it can break your
program. Program to the contracts provided by other
classes and packages, and you should have few or no
problems.I guess you are right. Maybe you can help me with the following problem (this is off this topic, I know): I have Swing JDK 1.2 and Swing from JDK 1.3. I have to register keys on components.
In JDK 1.2 I can use registerKeyBoardAction, in JDK 1.3 I have to use input maps and action maps. Both solutions only work with certain JDK. What I did was writing code which detects the java version and takes the appropriate action to register the keys. To make the thing compile in 1.2, I have to use reflection for the input/action map methods, because they are only available in 1.3.
Any idea how to solve this more elegantly ?

Run two java apps in separate jvm's on the same machine?

At the command line, when you type:
java MyClass
and then type:
java MyClass
are the two programs (assuming neither terminated prior to the other's execution) is it running in a separate Java Virtual Machine or the same one?
And if they're running in the same JVM, is there a way to run the second program in a separate JVM for testing purposes even though they're on the same computer? (btw I'm running windows XP).

thanks all...just a quick follow up question. Are two
separate jvm's on the same computer a good
representation of two jvms running on separate
computers?Don't know what you mean by "a good representation."
They're two separate processes. For basic testing, not worrying about performance, etc., and if your code doesn't do anything special to treat two VMs on the same box differently than two VMs on separate boxes, it's probably a reasonable approximation.

Multiple Java Apps in same JVM

Hi,
I have created a shell script which calls my java application with heap size as below:
/bin/java -Xms:3072M -Xmx:3072M ...
I'm calling the shell script multiple times in the background to create multiple instances of my java application in the same box. I have set a limit of 5 for java applications at any point of time. But what I'm experiencing is that first few sets of java application finish very fast (almost 3 mins) but last few sets taking a lot of time (around 10 mins). The quantity of data processed by all java applications is same but why later sets of java application is taking longer?
Can I do something here so that later sets of apps also completes in 3 mins? Can I refresh java heap before submitting another set of java applications? Java application is not mine but I have purchased from 3rd party. Please help!!!
Thanks in advance.

> why later sets of java application is taking longer?
Probably because of CPU usage. But could be memory.
>Can I do something here so that later sets of apps also completes in 3 mins
You tune the task, the complete task, to the box. That means you must understand in detail what is taking time and then architect that to make the best use of the available CPUs and memory (and other resources as used by the task.)

Running multiple java apps simultaneously, using different versions of jre.

I have a situation where I have 3 or 4 applications (and one applet) that were built over time, each with a different version of the jdk (ranging from 1.2.2.005 to 1.3.2). I need to know of a way (and it must exist) to run each of these applications on the same machine, and at runtime, have each application (or applet) run with its respective version of the jre. Certainly, one could change some source code and make all programs compatible with a particular jre, but that doesn't solve my problem if a new app is built with a new version of the jdk down the road. Currently, each runs fine by themselves, but if I try to run them together as different processes, some won't do anything because the default jre may not be what it needs. Would the Java Plug-in software have a role to play in this? Is there a way to specify (link) which application should use which jre?
P.S. These applications (right now) don't have to interact or interface in any way. I just need to have them all running as separate processes on the same machine and be able to jump from one to the other.

Write a batch file that sets the environment properly and restores it afterwards, here is a sample batch file we use which switches to IBM's JRE to run an app:
OLDPATH=$PATH
PATH=$PATH:"/usr/local/java/IBMJava2-13/jre/bin"
OLDCP=$CLASSPATH
CLASSPATH="/usr/local/java/IBMJava2-13/jre/lib/rt.jar:."
OLDHOME=$JAVA_HOME
JAVA_HOME="/usr/local/java/IBMJava2-13/jre"
# put the command to execute your program here
java -jar app.jar
PATH=$OLDPATH
CLASSPATH=$CLASSPATH
JAVA_HOME=$JAVA_HOME
This is for Linux, but it should be possible to write one for Windows too.

Multiple Java apps running in one VM

I have one VM that runs one application with GUI, database. It also spawns another VM to run more apps through Sockets.
Is there a way to run several Java apps within a single VM? If so, I can get rid of those interprocess communication stuff and make things easier.
Thanks in advance.
Lee

Yes you can do what to want to do. It is actually very benificail. Take a look at this article:
http://java.sun.com/docs/books/performance/1st_edition/html/JPClassLoading.fm.html#24732
here is code to do it as well:
package com.ist.system;
import com.ist.util.LogMsg;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.net.InetAddress;
import java.net.Socket;
* This class was pulled from:
* http://java.sun.com/docs/books/performance/1st_edition/html/JPClassLoading.fm.html#24732
* It was written to provide the ability to launch many applications in the
* same JVM. By doing this, it will save on system resources like RAM. When
* the <code>launch</code> method is called, it will check to see if there is a
* VM already running. If there is, it will launch the new application in the
* currently running VM. If there isn't, it will create a process that will
* keep a VM alive until there are no more applications running. Once there are
* no more applications running, this service will System.exit.
public class Launcher {
    static final int socketPort = 9876;
     * This method will launch a new instance of the passed in className
     * in an already running JVM if one is already running. If one is not
     * running, this application will create one.
     * @param className the class which you wish to launch
    public void launch(String className) {
        LogMsg.shortDebug("Trying to launch: " + className);
        Socket s = findService();
        if (s != null) {
            LogMsg.shortDebug("Launcher found service");
            try {
                OutputStream oStream = s.getOutputStream();
                byte[] bytes = className.getBytes();
                oStream.write(bytes.length);
                oStream.write(bytes);
                oStream.close();
                LogMsg.shortDebug(className);
            } catch (IOException e) {
                LogMsg.warn("Launcher couldn't talk to service");
        } else {
            LogMsg.event("Starting new service");
            Launcher.go(className);
            Thread listener = new ListenerThread();
            listener.start();
            LogMsg.shortDebug("Started service listener");
    protected Socket findService() {
        try {
            Socket s = new Socket(InetAddress.getLocalHost(),
            socketPort);
            return s;
        } catch (IOException e) {
            // couldn't find a service provider
            return null;
    public static synchronized void go(final String className) {
        LogMsg.shortDebug("Launcher running a " + className);
        Thread thread = new Thread() {
            public void run() {
                try {
                    Class clazz = Class.forName(className);
                    Class[] argsTypes = {String[].class};
                    Object[] args = {new String[0]};
                    Method method = clazz.getMethod("main", argsTypes);
                    method.invoke(clazz, args);
                } catch (Exception e) {
                    LogMsg.shortDebug("Launcher coudn't run the " + className);
        }; // end thread sub-class
        thread.start();
        runningPrograms++;
    static int runningPrograms = 0;
     * All programs wishing to exit should call this method and NOT
     * use System.exit. Calling System.exit will kill all the applications
     * running in this VM.
    public static synchronized void programQuit() {
        runningPrograms--;
        if (runningPrograms <= 0) {
            System.exit(0);
    public static void main(String[] args) {
        LogMsg.setupTraceLevel();
        Launcher l = new Launcher();
        l.launch(args[0]);
}

How to run multiple java files concurrently using command line?

Hi,
I have to write a script to run multiple java files and c files concurrently. Say, A and C are java files and B is another binary executable file, I have to make sure they are run in the order A-B-C, then I was trying to run by using
java A & ./B & java C
But it turned out that B could run before A started... Is there any way that I can ensure that A runs before B, and B runs before C by using the command line?
Thanks a lot.

GKY wrote:
Sorry, I didn't make my question clear enough...
A has to give some output files that B needs to get started,Then B can start at any time--even before A--and just wait for those files to be written. For instance, A could write to a temp file, then rename it to the real name. However, if there are multiple files, and they all have to exist, even this won't necessarily work. There are other approaches that will though.
although writing the output takes very short time,Depends on when the OS decides to give A CPU time, what else is going on on that disk controller and/or network, etc.
B could still run before A finishes the writing, As it can if you sleep for 1, or 10, or 1,000,000 seconds before starting B.
if B can't find the info it wants, it fails to move on. That's why I need to make sure A starts before B.No, you need to make sure A's data is there before B tries to use that data.
Edited by: jverd on Jul 29, 2008 1:06 PM

How to make a shortcut to run my Java app in Windows?

Hiya, Coders :-)
I am an absolute beginner.
I have copied a little window program from "Java 2 in easy steps".
I run it from the command line and a little window pops up.
I cannot find a way to start the app without the command prompt.
How can I make a shortcut to start it?
Julian (-_-)

Hiya, Coders ;-)
As it happens, I have a game from UJ Software: "Shisen for Java".
It has a shortcut, of course.
Here are all its details just in case it helps ...
The game folder is here:
C:\Program Files\UJ Software\Shisen for Java\jShisen.jar
Contents of the installed shortcut ...
General:
Type of file: Shortcut
Opens with: Java(TM) Platform SE binary
Location: C:\Documents and Settings\Julian Bury\Start Menu\Games
Shortcut:
Target Type: Executable Jar File
Target location: Shisen for Java
Target: "C:\Program Files\UJ Software\Shisen for Java\jShisen.jar"
Start in: "C:\Program Files\UJ Software\Shisen for Java\"
Run: Normal window
I don't suppose this will help.
It strikes me that nobody knows for certain how to run a java app!
I have two beginner's books, neither of which mentions anything beyond the command prompt.
Tricks to minimize the console window are just not professional!
The solution must be written authoritatively somewhere ...
has anyone seen it, please?
Increasingly disturbed ...
Julian *(-_-)*

Multiple applications on a single JVM

I was looking at some of the disadvantages of running multiple apps on a single JVM and then I came across this sentence which I donot totally comprehend. I guess somebody here would be able to shed some light
JVMs tend not to scale well past four processor configurations, which limits the viability of the single-JVM model on larger machines

It means a single JVM won't take as much advantageof
an 8 CPU system as multiple JVMs will.Yes I understand the lingual meaning of the sentence,
what I am struggling with is its semantic meaning.
Why can't a single JVM take advantage of 8 processor
r CPU? Are there any limitations associated with a
single JVM and in case there are what could they be?If I remember correctly the inherent concurrency limitations of JVM prevent it from fully utilizing the processing power of the machine. There is a limitation to the heap size one JVM can have, no. of thread pools that could be supported so multiple JVMs provide additional heap size, multiple thread pools, each corresponding to the application associated with the JVM, thus enabling to use the extra processing power.

Problem running my Java apps in my LG phone. Please help!

Hi all!!
I am quite new to the world of J2me, altough I've been coding Java for quite a few years now.
Recently I bought a LG u 8120 phone with Java-support so I decided it was time to step into the mobile Java-world.
Now I have written my first small app, a simple timer application which my phone (strangely enough) does not already have.
So what happens is this : I create my app on my PC and package it with the WTK into a jar -file and a jad-file which i transfer to the phone.
After this I can see the name of my app in the list of available programs in the phone. But when I try to run it: Nothing. The Java logo shows up for a few seconds and then I am tossed back to the menu.
I have thought of the following as possible problems:
1. the 8120 does not support MIDP2.0
2. I am doing something wrong transfering the files
3. I have missed out on one or several necessary steps in the process
Anyone who have developed Java apps for LG phones who can give me some hints?
I've used the Sun J2ME Wireless Toolkit 2.2 with MIDP2.0 and CLDC1.1 .
The apps works fine in the emulator. The problem starts when I want to run it in the phone. The phone I've tried is an LG u8120. LG apparently does not want to make life easy for its customers, so there is no support for transfering Java apps in the vendor-supplied software. I suppose that's because they want you to only download stuff from their site. However, after surfing around on some discussion forums for a while I found a program called G-thing which can be used to upload Java apps to LG-phones via USB.
Any help is very appreciated!
Thanks,
Sarah

Thanks,
I have tried this and ruled out some of the possible causes.
When I added some more exception handling, I could see that a "java.lang.IllegalArguenException" is thrown.
When I ran the AudioDemo package that came with WTK2.2 I noticed that the examples that uses WAV-files do not work while the rest works fine.
My new theory is now that the u8120 does not support the WAV-format, so I will try with an mp3 instead and see what happens.
Anyone who knows if LG-phones support WAV-format?
/Sarah

Multiple RMI servers in single JVM

Hi,
I have a RMI server listening to requests from internal network as well as external network. RMI returns the hostname as part of the stub. So to ensure that the subsequent RMI calls work fine I need to ensure that jama.rmi.hostname is set to correct value.
With 2 network IPs on 1 machine (internal & external), one option was to use a domain name as hostname and set it as java.rmi.hostname. Unfortunately, my client is not allowing use of DNS. So the hostname can be set only as an IP address.
Is there some way I can start 2 RMI servers in single JVM. While starting first one I can set hostname as internal IP and then while starting the other one I set hostname as external IP.
Problem is I don't know if such a solution can be setup. I read somewhere that from jdk1.4, System.setProperty("java.rmi.server.hostname", "172.25.17.41"); will set hostname dynamically. So all future requests will use the latest hostname.
Important thing is some way to make sure both networks can connect to my JVM through RMI.

I get it, you're going down the path I hate. I have undone this so many times ... (essential when deploying RMI Proxies).
Don't know why your intranet clients can't connect, unless it's the local binding of the server socket.
If you must explore this horrible kludge around a Sun kludge (and overload the SF mechanism even further), you may as well go the whole hog and have the SSF corresponding to each CSF bind its ServerSocket to the local address that you're going to embed in the CSF. Then you really know who can connect and who can't.
When writing SFs you need to think about what equality of socket factories really means. It only needs to imply that both socket factories being compared observe the same superimposed protocol (e.g. SSL), or that they both don't superimpose a protocol at all, so outbound or incoming calls really really can share the same port.
SF equality generally doesn't need to extend as far as whether the embedded host names (in your case - ugh!) are the same, or the port numbers if you want go the whole hog and bypass the stub's remote reference info altogether.

Why the constructor of the base class calls first when u run the java app.

why the constructor of the base class calls first when u run the java application

For the record the other very exciting questions are:
pls give the differences between application server and web server with examples
will u pls narrate the differences between servlet context and servlet config.....
where can we find servlet config...
is there any methods to access servlet config

Running a Java App like a service in linux and not closing with window

I know its not really a question i should ask you but thought you might have a quick answer for me, I have trying to running a small java application on one of the servers. I want it to run almost like a service, what i mean is i dont want the application to end when the terminal session is ended. So i thought i should put an entry into the /etc/rc.local file as follows (Final Line):
cd /home/bluepoint/Teamselect_ServerApp_v1.0/bin/
java Server
#!/bin/sh
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
touch /var/lock/subsys/local
/home/bluepoint/kmyfirewall.sh
su - bluepoint "/usr/local/tomcat/jakarta-tomcat-5.0.28/bin/startup.sh"
cd /home/bluepoint/startme.sh
As you will see it call a shell script which contains only the following lines (or see attached):cd /home/bluepoint/Teamselect_ServerApp_v1.0/bin/
java Server
but nothing happens when i restart the server. The DB, sendmail, tomcat etc start fine but not my app.
The application works fine if i start it in a terminal window so i know it can run.
Any ideas what im doing wrong??
Kind Regards

It's probably not happening because you missed the -c from the su command. However this isn't the correct approach to daemon processes on linux (which is what you're after).
What you need to do is to place a script in the /etc/init.d directory. This script should take a single argument and start the daemon if the argument is "start", and stop it if "stop". Check out the scripts already in there to see how it's done.
Then go to System Settings/Server settings/Services and enable the new service for the normal run level.

Running multiple java-apps in single JVM?

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