Junit test faild of lookup datasource

Hello,

I am trying to write a junit test case for JPA connection, but each time when i run the test case and it wil be failed at the following code.

ds = (DataSource) ctx.lookup("java:comp/env/jdbc/DefaultDB");

I searched the reason in google, but didn't find a good soluiton.

Do you guys faced the problem before? or someone could give me some suggestions.

My Testing Server is Local HANA Cloud

Thanks!

Bruce