Hi,
you can do this by calling:
<set name="userView">
<invoke name="checkoutView">
<ref>display.session</ref>
<ref>accountId</ref>
<new class="java.util.HashMap"/>
</invoke>
</set>
where accountId refers to the accountId of the user to retrieve.
Remark: if used for UI, checking out a view can last a looong time.
Regards
Stefan