[DBCP-71] [dbcp] Docs inaccurately describe default value of testOnBorrow

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed

Environment

Operating System: other
Platform: Other

• Bugzilla Id: 36799
• Assignee: Unassigned
• Reporter: Douglas Squirrel
• Created: 24/Sep/05 22:42
• Updated: 25/Mar/08 08:11
• Resolved: 25/Mar/08 08:11

Description

On the page http://jakarta.apache.org/commons/dbcp/configuration.html, the
Default column for the testOnBorrow parameter says that testOnBorrow is set by
default to "true". I observe from the behaviour of my application that this
seems to be true only if validationQuery is not set to null. Further, I find
this code in the BasicDataSource.java file, createDataSource method:
// Can't test without a validationQuery
if (validationQuery == null)

{ setTestOnBorrow(false); setTestOnReturn(false); setTestWhileIdle(false); }

Users may think that DBCP uses a default validationQuery such as "SELECT 1" if
you don't set one up explicitly, and that therefore setting testOnBorrow
without setting validationQuery is legitimate. This is what I naively thought -
although on reflection I can see why you don't, for reasons of portability.

It would be very helpful if the documentation explained this, with text like
this:
"The testOnBorrow, testOnReturn, and testWhileIdle parameters are defaulted to
true if and only if you supply a non-null value for the validationQuery
parameter."

It would be even more helpful if BasicDataSource noticed that testOnBorrow was
set to true without a valid validationQuery setting, and logged something like
"Disabling testOnBorrow, testOnReturn, and testWhileIdle because no
valiationQuery was supplied. To enable these settings you must also supply a
validationQuery, typically a very simple query like 'SELECT 1'".