# Adding java custom classes to Ignition 8.1

**URL:** <https://forum.inductiveautomation.com/t/adding-java-custom-classes-to-ignition-8-1/40835>\
**Category:** Ignition\
**Created:** [November 20, 2020, 12:24pm UTC](https://forum.inductiveautomation.com/t/adding-java-custom-classes-to-ignition-8-1/40835 "2020-11-20T12:24:59Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jiawei.liu](https://avatars.discourse-cdn.com/v4/letter/j/bb73d2/32.png) [@jiawei.liu](https://forum.inductiveautomation.com/u/jiawei.liu)\
**Post date:** [November 20, 2020, 12:24pm UTC](https://forum.inductiveautomation.com/t/adding-java-custom-classes-to-ignition-8-1/40835/1 "2020-11-20T12:24:59Z")

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Using Eclipse, I wrote a simple class for update database, and exported the jar file, put file into lib/core/common folder.  
I programmed a button script in the designer, and then can successfully call the class method, but it fail when execute “Class.forName(“com.mysql.jdbc.Driver”);” It seems that Driver cannot be found, but I have set CLASSPATH.  
Where am I doing wrong?

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 20, 2020, 1:31pm UTC](https://forum.inductiveautomation.com/t/adding-java-custom-classes-to-ignition-8-1/40835/2 "2020-11-20T13:31:08Z")

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JDBC drivers aren’t on the classpath in the Designer and Client.

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**Author:** ![jiawei.liu](https://avatars.discourse-cdn.com/v4/letter/j/bb73d2/32.png) [@jiawei.liu](https://forum.inductiveautomation.com/u/jiawei.liu)\
**Post date:** [November 23, 2020, 6:09am UTC](https://forum.inductiveautomation.com/t/adding-java-custom-classes-to-ignition-8-1/40835/3 "2020-11-23T06:09:48Z")

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That does it !!  
Thanks for the help!