When to open and close database connection
im trying to connect to a oracle database using servlets
when should i open and close the connection
it works fine when i do both in the doPost() method
but when i tried to open connection in init() methd .. it doesnt seem to work
what should i do...
the connection is initialised in the init() method but is null in the doPost() method
" im trying to connect to a oracle database using servlets
when should i open and close the connection
it works fine when i do both in the doPost() method
but when i tried to open connection in init() methd .. it doesnt seem to work
what should i do...
the connection is initialised in the init() method but is null in the doPost() method"
1:
without seeing the code i would say the the connection is null
because you are storing it as a servlet class variable which is
not thread safe.
2:
The best way to do it using connection pooling
detailed docs on the tomcat website
3:
if you are not using connection pooling, then
open and close the connection in the do* method
or
use init() to place the connection in the servletconfig
and close in destroy() and use synching to access
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