Update class files in eclipse

Hello there,

i want to know how do i update my class files of my java application in eclipse IDE.Appreciate your help.

Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

What do you mean by 'Update'? Class files are produced by the compiler when the source is compiled and that happens automatically by default in Eclipse
No, not automatically.

zolf:   Window-Preferences-General-Workspace.
See if the 1st and the 3rd checkbox are marked.

Well - it's always worked automatically for me (unless i've turned off default behaviour ;-) )
OWASP: Avoiding Hacker Tricks

Learn to build secure applications from the mindset of the hacker and avoid being exploited.

Hi Zolf,

What said by CEHJ, sciuriware are correct.
Here is the proof ;)
By default 'Build Automatically' is checked on. See the attached pic.
You can manually build projects(compile) using: Project > Build All

zolfAuthor Commented:

because i updated my java source code,then i jarred my application.with the update not reflecting when ii opened the application with the jar
Click the Project > Clean... option
and then build it again. Project > Build All


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
You may prefer to investigate using a build tool such as Ant or Maven to perform a clean compile before creating your application jar. Ant is probably the easiest to start using and integrates nicely with Eclipse.

For Ant start here:


Eclipse comes with Ant so you shouldn't need to install it again.
zolfAuthor Commented:
>> Window-Preferences-General-Workspace.
thanks for your suggestion.the third option was not selected in my case.

>>Click the Project > Clean... option
I managed to do this.But...
>>and then build it again. Project > Build All
i cannot select this.i mean it is not enabled.what could be the reason.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Editors IDEs

From novice to tech pro — start learning today.