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Analyze stand alone Java Application locally for threads

Respected Experts,
I have a stand alone java application and want to monitor the threads created by it. I am planning to use a tool like JConsole or JVisualVM. However, I am not able to connect these tools locally to my Java Application.
I am using Windows machine. JConsole and Java program are running locally. I have tried to run Java application with following JMV arguments with no success:
java -Dcom.sun.management.jmxremote.port=9999 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false LinkedListTest
When I try to connect using JConsole, my process id is greyed and following message appears:
Note: The management agent is not enabled on this process
I think I should be able to connect JConsole to a stand alone java application. Any thoughts what I am missing here
Thanks and Regards

Thanks for the inputs. I was able to solve the problem and the details are as follows:
As #Holger mentioned, both JConsole and JVisualVM can connect to the local Java Application running without any JMX arguments. The problem that I was facing was machine specific. I restarted the machine and deleted the following directory:
%TMP%\hsperfdata_User.Name
(I was not able to delete this directory without doing a restart)
Restarted JConsole/JVisualVM and was able to connect to local java processes using the process id.
In fact, the use of JVisualVM pointed me towards this fix. On start of JVisualVM, I got an error message stating something like local processes/applications can't be monitored. The message had a link to Troubleshooting guide. I am reproducing the relevant snippet:
Local Applications Cannot Be Monitored (Error Dialog On Startup)
Description: An error dialog saying that local applications cannot be monitored is shown >immediately after VisualVM startup. Locally running Java applications are displayed as Application> (pid ###).
Resolution: This can happen on Windows systems if the username contains capitalized letters. In >this case, username is UserName but the jvmstat directory created by JDK is >%TMP%\hsperfdata_username. To workaround the problem, exit all Java applications, delete the >%TMP%\hsperfdata_username directory and create new %TMP%\hsperfdata_UserName directory.
However, on my machine directory had the following format:
%TMP%\hsperfdata_User.Name
So, my recommendations are:
-check the name of the above mentioned directory for presence of camel case user name
-If not, follow the steps from the Trouble Shooting guide
-If the problem persists, delete the directory (may require machine reboot, as in my case)
-Restart JConsole/JVisualVM
Hopefully, the problem would be resolved.
Thanks and Regards

mysql jdbc communication exception

I have a Java application which initially reads 3 lakhs of data from my MYSQL database.Then it calls an API using an ExecutorService with newFixedThreadPool size=20.
After getting the response from the API it is inserting the responses to my DB.It is working fine for first 2000 rows(nearby).After that I am getting an error like following.
SQLError-com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The
driver was unable to create a connection due to an inability to
establish the client portion of a socket.
This is usually caused by a limit on the number of sockets imposed by
the operating system. This limit is usually configurable.
For Unix-based platforms, see the manual page for the 'ulimit'
command. Kernel or system reconfiguration may also be required.
For Windows-based platforms, see Microsoft Knowledge Base Article
196271 (Q196271).
Anyone could help me to fix this issue?

I was able to fix this problem by increasing the # of sockets that can be opened in Windows:
From the Windows Start menu, run the regedit.exe application
In the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters directory, create a new DWORD value named MaxUserPort with a decimal value of 65,000 (the default is 5,000)
After closing the regedit application, restart your computer.
(See also Increasing the number of Windows sockets or ports, Maximum Socket Connections)
A note of caution: When an application is using more than 5,000 socket connections, that may be an indication that system resources are not being used in a sustainable way. It would be good to investigate the root cause for why so many sockets are being opened simultaneously.

Problem running into java.net.bindexception cannot assign requested address

i am currently testing a server with an automatic test client that simulates a large number of users. Both the server and the client are written in Java. The client opens a tcp/ip connection for every user. Both the server and client run on Ubuntu linux, client runs on 11.04 and server on 10.04.
The testing went good up till 27000 concurrently open connections, after that i decided to jump to 36000 (the servers and clients resources weren't really all that used up at 27000 so i decided to make a slightly bigger jump). When i tried running the test for 36k i got the following exception on the client side:
java.net.BindException: cannot assign requested address
As far as i know at 36k i should still have free ports since not much else is running on either machine and tcp limits the port number at 2^16 which is 65536. Now since it is linux i also set the number of open files for the user to 100k with ulimit -n 100000.
But i am still getting the same exception.
I'm wondering what else could be a possible cause for the mentioned exception, or does linux in some other way limit the number of outgoing connections ?
Thanks in advance,
Danijel

By default, Linux picks dynamically assigned ports from the range 32768..61000. The others are available for static assignment, if you bind to a specific port number. The range can be changed if you want more of the ports to be available for dynamic assignment, but just be careful that you do not include ports that are used for specific services that you need (e.g. 6000 for X11). Also you should not allow ports < 1024 to be dynamically assigned since they are privileged. To check or change the range:
$ cat /proc/sys/net/ipv4/ip_local_port_range
32768 61000
# echo "16384 65535" > /proc/sys/net/ipv4/ip_local_port_range

A problem occurred when I tried to run a java web-app on server

I use eclipse for java EE as my IDE and tomcat as my server. Here's the problem:
Several ports (8080, 8009) required by Tomcat v5.5 Server at localhost are already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number.

It is as the exception says - you have a running instance of Tomcat (or, less likely, something else), that's taking ports 8080 and/or 8009. What to do:
if you've started tomcat, find it and stop it: using /etc/init.d/tomcat stop, or administrative tools > services > apache tomcat > stop, or shutdown.sh / shutdown.bat
if it is not you, find the process of tomcat and kill it (task manager on windows, and something like ps ux on nix)
if you don't find it, reboot

It looks like you have a Tomcat running already. It is possible that Eclipse couldn't stop Tomcat and now that it tries to run it again, it can't. Find and kill the existing process or reboot.

Issue the tasklist command in command prompt.
It should display tomcat as one of the processes. You can kill it by issuing either taskkill /IM "image_name" or taskkill /PID "process_id"

Others have mentioned that you could try and track down what's using those ports (perhaps another instance of Tomcat?), and kill it. However it might be that Windows itself is using them.
Killing the rogue program, or rebooting, might cure the problem for now, but to prevent this happening again, you need to reserve the ports you need. KB812873 explains how to do this.
Disclaimer: This KB article is for Windows Server 2003 and Windows 2000, and it's a while since I had to do this (for a few Windows Server 2003 installations). However I imagine it's the same for Windows 7. If not, someone will correct me :-)

Several ports (8080, 8009) required by Tomcat v5.5 Server at localhost are already in use.
You are not required to run Tomcat on 8080 or 8009. I am using Eclipse 8.6. I have set my Tomcat port to 8086 for eg.
Here are the steps to do it:
Stop Tomcat.
Click on the Run/Stop/Restart dropdown button
Select MyEclipse Tomcat
Click Configure Connector
Change port to whichever one you think is free.
To make sure you see these options make sure you have the latest version of MyEclipse.

Using the Netbeans 6.5 profiler to profile a remote web app?

I'm having trouble using the Netbeans 6.5 profiler to profile the memory usage of a java web app, remotely.
I have followed the steps in the tutorial, and was able to customize a Tomcat instance to start with the profiling agents. I can also attach the Netbeans profiler to the running server: for some seconds, the profiler shows graphs with the memory usage of the server.
However, I am not able to run my deployed web app. After a few seconds, the server is shut down gracefully as if it simply had reached the bottom of its method main (hardly the expected behavior of a web server).
During these seconds, the server is not responsible, and I can't connect to a web application in it, they are simply not deployed.
I do not want to import my app into a new Netbeans project just for profiling it. It's possible to profile a remote app without access to its source, right ? After all, for a few seconds, the server was running and being profiled.
I want to profile a web application in Netbeans 6.5. What did I forget ?

You can use VisualVM tool as well. Follow the below mentioned steps.
1) Run jstatd ( jstat demon process) ( Run on your remote machine where application is running)
jstatd -p 1098 -J-Djava.security.policy=tools.policy ( specify unused port ) if tools.policy file is not specified create it as follows.
tools.policy
grant codebase "file:${java.home}/../lib/tools.jar" {
permission java.security.AllPermission;
};
2) Also specify the following properties before you start your JVM.
#JMX property
JVM_ARGS="${JVM_ARGS} -Dcom.sun.management.jmxremote=true"
JVM_ARGS="${JVM_ARGS} -Dcom.sun.management.jmxremote.port=10992"
JVM_ARGS="${JVM_ARGS} -Dcom.sun.management.jmxremote.authenticate=false"
JVM_ARGS="${JVM_ARGS} -Dcom.sun.management.jmxremote.ssl=false"
3) Start the visual VM on local machine.
a. Under remote tab add remote node.
b. Wait for couple of minutes you will see all the core applications instance will be seen under remote tab.
c. Click on remote node then select Add JMX connections specify node:port (port mentioned above in point 2.)
d. Wait for few seconds you will see JMX connection under remote node.
4) After few seconds you will see new tab appearing under remote node. Double click on the remote_node:10992 you will see the profile table on right hand side.
You can see memory , cpu , thread etc details ..

Are profiling the entire webserver or did you use the profiling filter to profile only your package?
Reducing the interaction between the profiler and the app server itself can solve it.

Check your jvm version. The version used by netbeans should be same as that in tomcat.
Use default ports. If you have changed any ports ensure they are above 1024.
Try to profile the example application in tomcat (remove all other applications). If it is running sucessfully it means there is a memory constraint.
Profiling requires huge memory. use -xms1024m -xmx1024m for tomcat.
If every thing else fail. think of switching to jdk6 and tomcat 6.
After many trials I discoverd that there are lot of limitations in jdk5 and tomcat5. switching to tomcat6 and jdk6 solved the problem for me.
Profiling with netbeans does not work jrockit, ibm jdk etc..
--kiran.kumar