一、主類：

二、配置類：

三、singleton bean的創(chuàng)建流程
運(yùn)行到context.refresh();

進(jìn)入refresh方法：

向下運(yùn)行到紅線位置時(shí)：

會(huì)實(shí)例化所有的singleton bean.進(jìn)入finisheBeanFactoryInitialization方法：

向下拖動(dòng)代碼，可以看到beanFactory.preInstantiateSingletons();

進(jìn)入preInstantiateSingletons方法：

	public void preInstantiateSingletons() throws BeansException {
		if (logger.isTraceEnabled()) {
			logger.trace("Pre-instantiating singletons in " + this);
		}

		// Iterate over a copy to allow for init methods which in turn register new bean definitions.
		// While this may not be part of the regular factory bootstrap, it does otherwise work fine.
		List<String> beanNames = new ArrayList<>(this.beanDefinitionNames);

		// Trigger initialization of all non-lazy singleton beans...
		for (String beanName : beanNames) {
			RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
			if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {
				if (isFactoryBean(beanName)) {
					Object bean = getBean(FACTORY_BEAN_PREFIX + beanName);
					if (bean instanceof FactoryBean) {
						final FactoryBean<?> factory = (FactoryBean<?>) bean;
						boolean isEagerInit;
						if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) {
							isEagerInit = AccessController.doPrivileged((PrivilegedAction<Boolean>)
											((SmartFactoryBean<?>) factory)::isEagerInit,
									getAccessControlContext());
						}
						else {
							isEagerInit = (factory instanceof SmartFactoryBean &&
									((SmartFactoryBean<?>) factory).isEagerInit());
						}
						if (isEagerInit) {
							getBean(beanName);
						}
					}
				}
				else {
					getBean(beanName);
				}
			}
		}

		// Trigger post-initialization callback for all applicable beans...
		for (String beanName : beanNames) {
			Object singletonInstance = getSingleton(beanName);
			if (singletonInstance instanceof SmartInitializingSingleton) {
				final SmartInitializingSingleton smartSingleton = (SmartInitializingSingleton) singletonInstance;
				if (System.getSecurityManager() != null) {
					AccessController.doPrivileged((PrivilegedAction<Object>) () -> {
						smartSingleton.afterSingletonsInstantiated();
						return null;
					}, getAccessControlContext());
				}
				else {
					smartSingleton.afterSingletonsInstantiated();
				}
			}
		}
	}

可以看到實(shí)例化singleton bean的代碼：

可以看到對(duì)非abstract、singleton的、非懶加載的bean,則會(huì)調(diào)用getBean方法創(chuàng)建bean并緩存（getBean方法的流程不再詳述）
文章來(lái)源地址http://www.zghlxwxcb.cn/news/detail-600333.html

到了這里，關(guān)于spring復(fù)習(xí)：（50）@Configuration注解配置的singleton的bean是什么時(shí)候被創(chuàng)建出來(lái)并緩存到容器的？的文章就介紹完了。如果您還想了解更多內(nèi)容，請(qǐng)?jiān)谟疑辖撬阉鱐OY模板網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章，希望大家以后多多支持TOY模板網(wǎng)！