Spring原型引用单例

Question

I am using ConcurrentTaskExecutor to run the multiple tasks at the same time. By default in spring, it is scoped as singleton .

Here my taskExecutor is prototype and threadPoolExecutor is no.t

When requested a new taskExecutor is returned. My question is, since we are referring a threadPoolExecutor from prototype, will threadPoolExecutor be a new instance?

<bean id="taskExecutor" class="org.springframework.scheduling.concurrent.ConcurrentTaskExecutor" scope="prototype">
    <property name="concurrentExecutor" ref="threadPoolExecutor"/>
</bean>
<bean id="threadPoolExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
    <property name="corePoolSize" value="100" />
    <property name="maxPoolSize" value="200" />
    <property name="queueCapacity" value="1000" />
</bean>

Answer 1

The "prototype" keyword just means that each time you ask Spring for an instance, you will get a fresh instance. With the wiring you have, you are only asking once. So I expect that your taskExecutor bean will be a single instance.

Answer 2

No, the prototype keyword does not have "deep" scope. It does not apply to referenced or inner beans.

For the bean marked as prototype, ie taskExecutor , Spring will create a new instance every time you ask for it. But all those new taskExecutors will contain the same singleton instance of threadPoolExecutor .