JavaRanch Java in General (advanced)

Question about Design

Fri, 9 May 2008 09:36:58 MDT

Hello,

I am wondering which design would be better than the second for a business appliation managing user sessions (active/inactive etc):

1- Leave incoming threads to interact with sessions/database
2- Have internal threads managing incoming threads and serve their requests? How would I do that?
3- Any other idea is welcome.

Thanks!

Automatically detect an update in a file

Tue, 6 May 2008 20:04:51 MDT

Hi,

I just want to know what's the easiest way to do this? Let's have I have an XML file which is constantly being updated and the application needs to detect if this file is updated and transfer the updated contents of the file to a cache. My idea of doing this is running a thread which periodically checks the last update time of the file and if there is a change, then it will load the contents of the file into the cache, to update the cache. Is there a better and more efficient way of doing this? If my idea is the best idea, do you guys think spawning thread could handle this or should I stick to the more complex timing APIs such as Quartz?

Any feedback or help would be appreciated. Thanks

best way to compress in GZIP serialized objects in MEMORY

Tue, 6 May 2008 12:38:50 MDT

Hello,

I am looking for sample code to compress a serialized object in the memory (in a form of ByteArray or whatever) Say, Object o is the serialized object and i need to turn it into another Object z (compressed) as another variable. Do you have a sample?

Thanks!

To display ChangeLog results in peculiar scenario

Mon, 5 May 2008 06:48:47 MDT

Hi

I have the tables called,USERROLES and USERROLE_ADT, In my application,User has some set of roles assigned. Administrator can add or delete the roles.

Whenever he modifies the role, we are deleting the all roles and inserting the roles newly(As we can't update the USERROLE table due to some database integrity).

Now i need to display the changelog for the userroles, whenever roles are changed for the user, we need to display those details are in below format

field currentvalue oldvalue changed date change by

role1 active deleted today(dd/mm/yyyy) adminName
role2 deleted active yesterday(dd/mm/yyyy) adminName2

Could any one comeup...

Can I control Keybord from voice ?

Sat, 3 May 2008 01:48:30 MDT

I'm currently starting my final year of Software Engineering degree.I've decide to implement software to handle keyboard from voice for disable people as my final year project.So i want to know will this possible to implement and also need your ideas to get more easier to do this for me.
Thank you
Kasun Chandrasiri

How to parse a Java source file

Fri, 2 May 2008 07:22:28 MDT

hi friends,

Can any one let me know how to parse a .java file and extract class names, method names, parameter list etc.. from the file.

handling Java child process execution

Fri, 2 May 2008 05:06:27 MDT

Hi,

I am executing a shell script using java program on unix platform.
I am using Runtime.exec(shell_script_name) method to execute it.
A shell script uses prstat command & it gives well formated output to my java program.
But, the problem is that the prstat command doesn't get killed by unix os.
so that , when ever I execute the script each time a new instance of prstat is seen as a new process using ps -fu command. & this prstat process seen even when java program is stopped.

please, help me so that prstat command execution should get stopped just after script execution finished.

Thanks

Amit Pandit

Getting inner class functionalities without using INNER CLASS

Wed, 30 Apr 2008 04:50:21 MDT

can anybody tell me, how can we achieved the functionality of INNER class without using INNER CLASS?

Inner and Abstract class

Wed, 30 Apr 2008 01:34:20 MDT

Hi all

Is it legal(not in terms of syntax) to define inner class inside abstract class does it comes under any design pattern?

Getting Rid of Redundant Jars.

Mon, 28 Apr 2008 14:22:16 MDT

How can I determine which all classes and jars my Java program is referencing
from a all the jars in class path ?

Problem in Uploading Files

Wed, 23 Apr 2008 09:07:59 MDT

On uploading large files of size(290 Mb).
It is getting Failed to parse multipart file.
" MultipartParseException "
When trying to upload small files of about 5K it is ok and uploading.
My browser is IE.7.But in the InternetOptions setting the JRE used is 1.5.
If the JRE used is 1.6 the upload of large files wont work ,the page will be in progress for a long time
and after that it will show Timeout without uploading the file.
I am using enctype=multipart/form-data in the file for upload.
But in jre1.6 it is not supporting.
Can any one help me to solve this problem.

java.io.zip cannot uzip what it zips

Thu, 17 Apr 2008 03:29:26 MDT

My problem began deploying a war file in tomcat. I get the error:
java.io.FileNotFoundException: C:\MyWorkSpaces\X\A Swing Help System with CreateWebHelp_files\image001.png (The system cannot find the path specified)

The file is in the war file and if I change the extension to zip, WinZip constructs the directory correctly. If I zip the original directory wit WinZip, it deploys fine in Tomcat.

Tomcat uses java.io.zip to unzip, so i created a program to unzip and i get the same error. The code is:

code:


public void unZip(String directoryName, String fileName) throws Exception {
this.unzipDirectory = directoryName;
this.dirsMade = new TreeSet<String>();
this.w...

How to run a java File using RunTime

Thu, 17 Apr 2008 01:49:03 MDT

I have java file which is running on Websphere Application Studio (WSAD). From the Java file i need to invoke a java file to run as like it runs on command prompt. So what i did is i got the RunTime instance and tried to execute the java file like

Runtime.getRunTime.exec("java -cp classpath JavaFilename);

the system was not showing any result or error. Please help me to get it resolved and run the java file

How to run a java File using RunTime

Thu, 17 Apr 2008 01:35:03 MDT

Problem in Bean Design

Wed, 16 Apr 2008 07:17:01 MDT

I am developing a project as Task Tracking System.One of the entities used in my project are Client and Task.So i build the bean for Client and Task.
The Client Bean consists:Client Id,ClientName,ClientStatus.The Task bean consists of TaskId,TaskName,Description,CreateDate,TaskStatus etc.The Relation between client and task is of one to many relation.So I include Clientid in Task Bean.Now i want to show the list of task with their client as

ClientName ClientStatus TaskName CreateDate TaskStatus....

For this i am getting the above data from the database .Now i want to set the bean properties after getting the resultset from the database.Now the problem is that which bean property should i set.If i set the Task pr...

accesing data from an IP address new

Wed, 16 Apr 2008 07:17:01 MDT

Yes all those computers are having ftp access.Do I need to configure my webserver for accesing data on those machines for reading files on those machines or IP addresses.How to do it?
Give some example.Like my web application is deployed on the webserver using JSF on Netbeans with Visual Web Pack.How to access the files in the specified directories on those machines simultaneously like my web application should be able to fetch data from the files on those machines after every 2 secs and upload that data to the database.

Please reply ASAP.

accesing data from an IP address new

Wed, 16 Apr 2008 07:15:00 MDT

Problem in Bean Design

Wed, 16 Apr 2008 06:29:00 MDT

accesing data from an IP address new

Wed, 16 Apr 2008 06:19:00 MDT

accesing data from an IP address

Wed, 16 Apr 2008 03:27:00 MDT

Suppose I have developed a web application which is deployed on the webserver, now our LAN has 6 computers attached.IP Addresses of these computers is known to me. Now this application will keep on fetching the data after every 2 secs from all the PCs in this network, go to a particular folder in each of the computers and read the most recent file and upload its details to the database simultaneously.How to build this kind of application? Totally in a confused state of mind.Some code snippets or tutorials will be of great help.Please reply ASAP.

accesing data from an IP address

Wed, 16 Apr 2008 03:25:00 MDT

accesing data from an IP address

Wed, 16 Apr 2008 03:09:00 MDT

accesing data from an IP address

Wed, 16 Apr 2008 02:05:00 MDT

CPU utilization in java

Wed, 16 Apr 2008 00:27:00 MDT

Hi

I want to show CPU utilization in my application using java code.
The code should be OS-independant. Any workarounds are also welcome.
I don't want to use JNI.

can anybody help me in doing that.

Regards

Amit

wait() vs sleep()

Tue, 15 Apr 2008 22:58:59 MDT

Hi,
what is the difference between wait() and sleep() in threads.

wait() vs sleep()

Tue, 15 Apr 2008 22:56:59 MDT

Hi,
what is the difference between wait() and sleep() in threads.

A curious (Non Java) Question

Tue, 15 Apr 2008 19:54:59 MDT

I cant help but notice that most if not all the topics in this part of the forum are closed or are closed as soon as they are created. I am just a little curious why?

No offence meant

Oh, and by closed I mean that they are locked against further editing

A curious (Non Java) Question

Tue, 15 Apr 2008 18:04:59 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 14:06:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 13:04:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 13:02:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 12:52:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 12:40:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 12:36:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 12:18:58 MDT

A curious (Non Java) Question

Tue, 15 Apr 2008 12:16:58 MDT

I cant help but notice that most if not all the topics in this part of the forum are closed or are closed as soon as they are created. I am just a little curious why?

No offence meant

CPU utilization in java

Tue, 15 Apr 2008 10:56:58 MDT

CPU utilization in java

Tue, 15 Apr 2008 09:40:58 MDT

CPU utilization in java

Tue, 15 Apr 2008 09:36:58 MDT

how to speed up Java program?

Tue, 15 Apr 2008 09:20:58 MDT

I know there is way by which we can speed up our Java programs.
what's that I don't know.
please give some lights.

best regards,
omi

how to speed up Java program?

Tue, 15 Apr 2008 09:12:58 MDT

I know there is way by which we can speed up our Java programs.
what's that I don't know.
please give some lights.

best regards,
omi

CPU utilization in java

Tue, 15 Apr 2008 08:48:58 MDT

CPU utilization in java

Tue, 15 Apr 2008 08:44:58 MDT

CPU utilization in java

Tue, 15 Apr 2008 07:41:20 MDT

Reading a file that has .ODT extension

Tue, 15 Apr 2008 03:05:19 MDT

i have created the file using Openoffice .org .When i read the file Its giving the junk value.Are there any api to read the content of the file that has extension of .ODT

Thanks a Lot For helping in advance

Change the JVM default ClassLoader

Mon, 14 Apr 2008 08:55:17 MDT

Hi, someone knows how it's possible to substitute the default JVM ClassLoader with a new one? I would like to do this from outside the source code, maybe there exists some command line option doing this.

Thanks in advance

its internal server error

Sat, 12 Apr 2008 00:45:10 MDT

500 (SC_INTERNAL_SERVER_ERROR) is the generic server is confused
status code. It often results from CGI programs or (heaven forbid!)
servlets that crash or return improperly formatted headers.

Java and MSMQ

Fri, 11 Apr 2008 07:29:08 MDT

I've been tasked with identifying some 3rd party bridge which will allow us to access MSMQ via java WITHOUT writing loads of JNI (we have a simple bridge at the moment which allows us to do very simple things with MSMQ but it is proving a maintenance nightmare).

Has anybody managed to integrate Java and MSMQ, and if so how was this achieved????