ORA-01000: maximum open cursors exceeded tips

I am getting following error.
I made a combo box with select query behind it, i used itemlistener to fetch data. Today during testing i found that if user move too quickly in combo box so select query will be fired for each number he passes and it gives an error. So what does it mean and how to resolve it... Thank you in advance.

Connect to the database as SYS and execute this query

ALTER SYSTEM SET open_cursors = 400 SCOPE=BOTH;

or

set in the init.ora file parameter open_cursors, for example

open_cursors=400

and restart database

instead of 400 set as you want

actually default open_cursors are set to 300 in oracle database so you can change it to how much open_cursors you want so try the following query
sql>alter system set open_cursors=500 scope=BOTH(as your wish how much open_cursors you want you just specify next to open_cursors column)