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using an external Jar / referenced library [message #1797061]

Wed, 24 October 2018 11:53

Eclipse User

Appreciate any support on this (after reading many forums I am none the wiser).

If if I put a jar into (Neon.3) WEB-INF/ lib folder then I can import a class from that jar (in my jsp) and run a method against that class.

If however I do not want that jar packaged within Eclipse (I want it to remain completely external) then I add a library linked to that jar and the jar then appears in Referenced Libraries, as expected, but the original import then fails (class / jar no longer found) and I cant run that class. The qualified name is the same.

I can manually open the package and view the class file so I know it is there.

I don't want to have to embed my jar in the Eclipse project because that jar already runs as a 'stand-alone' back-end process, I just want to ensure jsp's in Eclipse can call it / run threads etc.

Is this possible, do I have to move the jar to a different folder?

Regards
Active.

Re: using an external Jar / referenced library [message #1797070 is a reply to message #1797061]

Wed, 24 October 2018 14:59

Eclipse User

It's more possible that you need to Validate the JSP again from the file/project context menu. Some changes to the Java Build
Path won't kick off an automatic revalidation.

Also, Neon.3 is no longer the current release. You should upgrade if possible.

Re: using an external Jar / referenced library [message #1797076 is a reply to message #1797070]

Wed, 24 October 2018 16:33

Eclipse User

Thanks Nitin for the prompt reply.

Though I always clean / validate as a matter of course after every change and have restarted Eclipse, cleared old files files from lib etc just to be sure.

There are a number of messages and various forums which indicate that something seems to 'break' when external jar's are used (the only solution to this is to import them into the default package).

For example -

"I found that you have to put your .java file in the default package. For example, you will get errors if you put your java code in a package like com.xxx.yyy.ccc" (something which I cant do, the package in my case must commence com. etc as it runs as an existing back-end java process)

I will check for Eclipse updates though I downloaded only a couple of weeks ago and I seem to remember that the latest version had some sort of java comparability issue, hence I used Neon which I am (was) familiar with and is stable on another PC.

Regards
Active

Re: using an external Jar / referenced library [message #1797080 is a reply to message #1797076]

Wed, 24 October 2018 18:10

Eclipse User

External jars, by default, won't be deployed to the server, but I really have no idea
why using a package name would be an issue. Maybe they had their project set up
incorrectly.

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