java ee - Difference between database connection through session bean and entity bean -

what difference between writing jdbc (or) hibernate connectivity code in ejb3 session bean , writing same connectivity code through ejb3 entity bean(jpa). please clarify this..

both allow write java gets data in , out of databases, actual coding different.

jdbc lets write sql code

 insert  ... 

or

 select  ... 

you have write own code transfer data between java objects , jdbc code. end lots of repetive "put field in column" kind of code.

have @ examples such link text flavour.

in jpa/hibernate annotate java class instructions tables , columns fields correspond to. reduces amount of code need write.

it's simple example (taken this jpa example:

@entity public class inventory {     @id     protected long id;     ...     public void setitem(item item) {         this.item = item;         this.id = item.getsku();     }     ... } 

i session bean + jpa considerably less effort session bean + jdbc.