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.

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basav_comConnect With a Mentor Commented:
Click the Project > Clean... option
and then build it again. Project > Build All

CEHJConnect With a Mentor Commented:
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
sciuriwareConnect With a Mentor Commented:
No, not automatically.

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

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Well - it's always worked automatically for me (unless i've turned off default behaviour ;-) )
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
cwrdy12Connect With a Mentor Commented:
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.
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