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javaspringspring-3spring-aoppool

How to let CommonsPoolTargetSource pool size grow as needed?

I noticed that when there are many requests and the max pool size is reached, other requests wait until a resource is free. How do I setCommonsPoolTargetSource such that when it reaches its max pool size, new object instances will be created? The excess resources must also be release after it's used.

Initially, I tried looking for a minSize property but found out that CommonsPoolTargetSource does not have a minSize property. Below is the body of my web.xml:

<bean id="simpleBeanTarget" class="com.bean.SimpleBean" scope="prototype">        
</bean>

<bean id="poolTargetSource" class="org.springframework.aop.target.CommonsPoolTargetSource">
    <property name="targetBeanName" value="simpleBeanTarget" />
    <property name="maxSize" value="3" />
    <!-- How do I let the pool grow if more than 3 instances is needed? -->
    <!-- And how do I release the excess instances after usage? -->
</bean>

<bean id="simpleBean" class="org.springframework.aop.framework.ProxyFactoryBean">
    <property name="targetSource" ref="poolTargetSource" />
</bean>
Solution

  • Try <property name="whenExhaustedActionName" value="WHEN_EXHAUSTED_GROW" />

    or 

    <property name="whenExhaustedAction">
 <util:constant static-field="org.apache.commons.pool.impl.GenericObjectPool.WHEN_EXHAUSTED_GROW"/>
</property>