Java Decompiler (Jad) JD-GUI

Jad (Java Decompiler) is a currently unmaintained decompiler for the Java programming language. Jad provides a command-line user interface to extract source code from class files. One of the popular Java Decompiler is JD GUI.

Find Java class or text file in jar files using JarScan

Probably we all face ClassNotFoundException and we want to know where is that following class is missing with in our jars.  You will search hundreds of jar files to find that specific class.  jarscan is helpful tool or utility to look over your required class with in any archive.  jarscan searches recursively all archives in the current directory and all subdirectories for certian entry. 

lsof Command

lsof is a command meaning "list open files", which is used in many Unix-like systems to report a list of all open files and the processes that opened them.

As we all know Linux/Unix considers everything as a files (pipes, sockets, directories, devices etc). One of the reason to use lsof command is when a disk cannot be unmounted as it says the files are being used. With the help of this command we can easily identify the files which are in use.

ulimit Command

The ulimit command is a built-in shell command, which displays the current file size limit.  The default value for the Maximum file size, set inside the kernel is 1500 blocks.  

More details about eclipse.ini

Let see more details about eclipse.ini

Eclipse startup is controlled by eclipse.ini file which comes by default installation under ECLIPSE_HOME/eclipse.ini.

Under eclipse.ini file we can provide JVM agruments and startup arguments and lauching libaries and etc.

Let see the default eclipse.ini file.


JMap is java utility to create core file or heap dump running java process id. To describe bit more it prints shared object memory maps or heap memory details of a given process or core file or a remote debug server

Let see what different options we see from Jmap.

You will find jmap.exe under %Java_Home%/bin/

VI Editor Part Three

Let continue VI Editior other commands which are more useful and very important

Closing and Saving Files

This Section will give details about of saving files during quitting VI editor.

Quitting and Saving File

VI Editor Part Two

Let continue VI Editior other commands which are more useful and very important

Basic Editing

To use editing commands we must be in command mode.  Following

VI Editor Part One

The VI editor (Visual Editor) is screen editor which is almost similar in all Unix based OS (Operating System).  Once we are used with them then you will feel vi editor are easy and very powerful during editing in all Unix based OS.

Let see how to start an vi editor in Unix system.

JRockit Thread Status

This Article will help you to understand different states and status of thread in Jrockit Thread dump.

Thread Status are defined in three ways.
  • Life States
  • Run States
  • Special States

How to take thread dump from JBoss Server

Here are ways to get the thread dump for your JBoss server for performance analysis.

In this article we will see three different ways to take thread dump from JBoss Server.

How to take Thread dumps from IBM Websphere

Here are ways get the thread dump for your Websphere (WAS) server for performance analysis.

The most reliable way to generate a thread dump in WAS is using wsadmin utility and through Script . The steps for the same are as follows:

How to take Thread Dump from Weblogic

We checked how to collect thread dump in standard way from OS and now we will try to learn how to collect thread dumps from various Application Server’s and their Utility.

Now we will learn how to take thread dump using Oracle Weblogic Server and it’s Utility.

How to take a Thread Dump from different OS

How can we take thread dumps from a JVM on Unix or Windows?

Before know how to collect thread dump in various OS and App Server let see what thread dump is.