Set Custom Date Format in SQL Developer.

You can change this in preferences:

1. From Oracle SQL Developer's menu go to: Tools > Preferences.
2. From the Preferences dialog, select Database > NLS from the left panel.
3. From the list of NLS parameters, enter DD-MON-RR HH24:MI:SS into the Date Format field.
4. Save and close the dialog, done!

Here is a screenshot:

Accessing Services in Windows.

There are two ways to view Services on your computer. The first is to use the MS Configuration Utility by typing msconfig.exe in the Run box accessed via the Start Menu, followed by clicking the Services tab. If you want a quick visual of which items are running or stopped.

The preferred way to make changes to services is to launch services.msc from the Run option on the Start Menu. The Services window shown below will open. From here you can stop , start or restart a service. This can be useful if you are using a MySQL, Tomcat or other services which you may want to start or stop or restart. You can just create a shortcut to the Desktop which is a easy way to access services.

Difference between the Eclipse Packages.

what are the differences between the following packages:

Helios Packages
Galileo Packages
Ganymede Packages
Europa Packages

This is a question of version.

Here's a quick reference on Eclipse releases and names.

	3.0	28 June 2004
	3.1	28 June 2005
	3.2 Callisto	30 June 2006
	3.3 Europa	29 June 2007
	3.4 Ganymede	25 June 2008
	3.5 Galileo	24 June 2009
	3.6 Helios	23 June 2010
	3.7 Indigo	28 June 2011

How to make a Build.xml in Eclipse ?

Making a Build.xml in eclipse is very easy and it can be done in just a few button clicks.

After you have made the project and kept all the source files in the src folder do the following steps to make a build.xml .

• Right click on the Project folder and click on Export.
• Click on General which has a option Ant Buildfiles.
• Click next and select the project for which you have to make a Build.xml .
• This will create the Build.xml.

Now if you want to clean or build the project do the following steps:

• Right Click on the the Build.xml file and click on Run As.
• Click the Ant Build.. option which will take you to Edit configuration and launch.
• You can select target to execute.

Video Reference : https://eclipse-tutorial.dev.java.net/visual-tutorials/generatingantbuildfile.html

Windows cannot find '-Dsun.io.useCanonCahes=false'

Windows cannot find '-Dsun.io.useCanonCahes=false'. Make sure you typed the name correctly, and then try again. To search for a file , click the Start button, and then click search.

If you have the following error while you are trying to start the Apache Tomcat server ( My case it was Apache-Tomcat-4.1.37 ). Then you don't have the JAVA_HOME correctly added to the environment variable.

• Right click on My Computer and click on properties.
• Go to the Advanced tab and click Environment Variables.
• Add a new entry to the system variables if the JAVA_HOME does not exists.
• Set the variable value pointing to the place where it is installed.

To compile any of the .java file you can open the command prompt and type

javac classname.java

This will create the classname.class file .

But if the path to the javac compiler is not set the nit will give the following error message although the JAVA_HOME is set:

"'javac' is not recognized as an internal or external command, operable program or batch file."

To rectify the problem add the path of the javac to the path in the Environment variables.

C:\j2sdk1.4.2_18\bin

The other work around to this problem is each time specify the path like:

C:\j2sdk1.4.2_01\bin\javac classname.java

But setting the environment variables is better option.

Creating dependencies between the Projects.

• Right click on the project you are working on.
• Go to Properties which will open a Properties window.
• Go to the Java Build Path.
• Do Add Folder to add new folders to which have dependiencies.
• You can add the Libraries also.

Taking the Snapshot of the frontmost window in Windows

Pressing Alt-PrintScreen (Alt-PrtScrn) places an image of the frontmost window on the clipboard. Pressing PrintScreen by itself places an image of the entire desktop on the clipboard.