jsp unable to put session attribute into string

Question

i'm having an issue with a session attriblute in a jsp page, i would like to pass it into a string so that i can use it to query a database eg,

String group=session.getAttribute("group");

i know it has been correctly populated because if i put the below in a page it displays the correct value

<%=
session.getAttribute("group")
 %>

the error i am getting is

Type mismatch: cannot convert from Object to String

is there a different way to put a session variable into a String? or am i doing it completely wrong. any assistance much appreciated.

What is the `session` variable ? How do you get it ? Is it `HttpSession` ? — AllTooSir, Jul 09 '13 at 10:33

score 13 · Accepted Answer · answered Jul 09 '13 at 10:24

13

You have to cast it to String

String group=(String)session.getAttribute("group");

where session.getAttribute("group"); returns Object.

answered Jul 09 '13 at 10:24

Suresh Atta

1

i tried changing by code like you said but now get "string cannot be resolved to a type" – user2168435 Jul 09 '13 at 10:29
2

@Baadshah don't you think that import is default. I think its a typo. – Subir Kumar Sao Jul 09 '13 at 10:31
@SubirKumarSao yes.But I just make him cross check :) and finally he caught that typo. – Suresh Atta Jul 09 '13 at 10:34
@user2168435 No issues.Happens to every programmer :) – Suresh Atta Jul 09 '13 at 10:36
i prefer `String group=session.getAttribute("group").toString();` – MaVRoSCy Jul 09 '13 at 10:42
@MaVRoSCy yes you are right ,but casting to a String is cheaper since that doesn't require an external function call, just internal type checking. – Suresh Atta Jul 09 '13 at 10:45

score 1 · Answer 2 · edited May 23 '17 at 11:54

session.getAttribute(String name) will return an Object.

To be safe and prevent any accidental ClassCastException, I would use String.valueOf(Object obj), like this:

String group = String.valueOf(session.getAttribute("group"));

Sources:

score -2 · Answer 3 · edited Dec 13 '15 at 11:52

-2

you just put like this:

String group=""+session.getAttribute("group");

append as string, simple.

edited Dec 13 '15 at 11:52

Jiri Tousek

answered Dec 13 '15 at 08:08

007

3 Answers3