Tomcat jdbc connection pool, does not release connections after using

Question

What may be reason for tomcat does not release connections after using?

Herem is my config

<Resource name="jdbc/DataSource" auth="Container"
type="javax.sql.DataSource" username="))" password="))"
driverClassName="oracle.jdbc.driver.OracleDriver"
url="))"
factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
initialSize="55"
maxActive="55" maxIdle="55" maxWait="15000"

testWhileIdle="true"
testOnBorrow="true"
testOnReturn="false"
validationQuery="SELECT 1 FROM DUAL"
validationInterval="20000"

timeBetweenEvictionRunsMillis="30000"
removeAbandoned="true"
removeAbandonedTimeout="60"
/>

Answer 1

You still need to call connection.close() in your code to have the connection released to the pool. It does not happen automatically.

You can configure the pool to detect "left over connections" wiht:

removeAbandoned="true"
removeAbandonedTimeout="60"

connection inactive for longer than given number of seconds will be closed automatically and recycled by the pool

Answer 2

The most probable is that you don't close connections after using them. It can happens for example if you don't manage correctly exceptions.