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Showing posts from February, 2009

Useful list of Java resources

I came across this article titled "Essential Java Resources" in developerWorks and found out to be useful.

Gotchas with DBCP

I had to make use of DB connection pool in one of the applications that I was implementing. Since I am new to Java, everyone in the team was suggesting why don't you make use of Commons DBCP. Being a fan of reuse, I decided to make use of DBCP and started reading about the parameters that are exposed so that I can customize DBCP to fit my needs.

While reading through the available configuration parameters, I was thinking, "I don't need to check the connection to be bad on every borrow or return. It is sufficient if I check for being bad only when the connection is sitting idle in the pool." So I set the testWhileIdle to be true and set the validationQuery to be "SELECT 1 FROM DUAL". I was thinking that the configuration that I had was the optimal for the situation in hand.

But one thing I overlooked was, the default value for the testOnBorrow is true. So the moment you set the validationQuery to be any non-null value, every connection you borrow from the pool…