java - Implement a method that generates the last insert id -

i'm using jpql , want implement simple methode generate last insert id table test.

    public integer lastinsertid(){     string jpql="select t test t id=:last_insert_id()";     query query=entitymanager.createquery(jpql);     return ; } 

if want last id, given id's generated sequentially, this:

em.createquery("select max(t.id) test t", integer.class).getsingleresult();