spring 线程池疑问？

Question

哪位大神知道 spring封装的线程池 源码里面

ExecutorConfigurationSupport
成员变量
private ExecutorService executor;

ThreadPoolTaskExecutor类 继承ExecutorConfigurationSupport类

成员变量
private ThreadPoolExecutor threadPoolExecutor;
方法
protected ExecutorService initializeExecutor(
ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler) {
BlockingQueue queue = createQueue(this.queueCapacity);
ThreadPoolExecutor executor = new ThreadPoolExecutor(this.corePoolSize, this.maxPoolSize, this.keepAliveSeconds, TimeUnit.SECONDS,queue, threadFactory, rejectedExecutionHandler);
if (this.allowCoreThreadTimeOut) {
executor.allowCoreThreadTimeOut(true);
}
this.threadPoolExecutor = executor;
return executor;
}

ThreadPoolTaskExecutor任务执行是采用的自身成员变量
private ThreadPoolExecutor threadPoolExecutor;

那么父类ExecutorConfigurationSupport的成员变量private ExecutorService executor;虽然初始化了，实际没有用到

请问这里面是什么原因？

ExecutorConfigurationSupport类初始化方法
public void initialize() {
if (logger.isInfoEnabled()) {
logger.info("Initializing ExecutorService " + (this.beanName != null ? " '" + this.beanName + "'" : ""));
}
if (!this.threadNamePrefixSet && this.beanName != null) {
setThreadNamePrefix(this.beanName + "-");
}
this.executor = initializeExecutor(this.threadFactory, this.rejectedExecutionHandler);
}
抽象方法由子类ThreadPoolTaskExecutor实现
protected abstract ExecutorService initializeExecutor(
ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler);

Answer 1

父类中的executor 是用到的：
[code="java"] public void shutdown() {
if (logger.isInfoEnabled()) {
logger.info("Shutting down ExecutorService" + (this.beanName != null ? " '" + this.beanName + "'" : ""));
}
if (this.waitForTasksToCompleteOnShutdown) {
this.executor.shutdown();
}
else {
this.executor.shutdownNow();
}
}

[/code]
用于停止executor时使用

ThreadPoolExecutor是池化的Executor实现，我们可以实现其他的；

就像struts2的Action 与 ActionSupport一样，ActionSupport提供了如验证、国际化的功能，我们可以复用它，但不一定使用它