cyxCoder

 //以注解的方式执行
ApplicationContext context = new AnnotationConfigApplicationContext(MySpringConfig.class);
        

	/**
	 * Create a new AnnotationConfigApplicationContext, deriving bean definitions
	 * from the given component classes and automatically refreshing the context.
	 * @param componentClasses one or more component classes — for example,
	 * {@link Configuration @Configuration} classes
	 */
	public AnnotationConfigApplicationContext(Class<?>... componentClasses) {
		this();//初始化类
		register(componentClasses);//对配置类进行注册
		refresh();//手动刷新
	}

• 读取注解bean信息读取类（AnnotatedBeanDefinitionReader）；
• bean类扫描器（ClassPathBeanDefinitionScanner）；

源代码如下：

	private <T> void doRegisterBean(Class<T> beanClass, @Nullable String name,
			@Nullable Class<? extends Annotation>[] qualifiers, @Nullable Supplier<T> supplier,
			@Nullable BeanDefinitionCustomizer[] customizers) {
		//注解方式启动的配置类 注入IOC bean信息（即为@Configuration注解的类注入容器）
		AnnotatedGenericBeanDefinition abd = new AnnotatedGenericBeanDefinition(beanClass);
		//判断注解配置类是否使用条件注册（即符合@Condition注解的条件）
		if (this.conditionEvaluator.shouldSkip(abd.getMetadata())) {
			return;
		}
		//设置回调方式
		abd.setInstanceSupplier(supplier);
		//判断config类上是否有加上@scope作用域
		ScopeMetadata scopeMetadata = this.scopeMetadataResolver.resolveScopeMetadata(abd);
		//设置scope
		abd.setScope(scopeMetadata.getScopeName());
		//有beanName用beanName，没有生成一个
		String beanName = (name != null ? name : this.beanNameGenerator.generateBeanName(abd, this.registry));
		//对一些通用注解进行处理：Lazy、Primary、DependsOn、Role、Description
		AnnotationConfigUtils.processCommonDefinitionAnnotations(abd);
		if (qualifiers != null) {
			for (Class<? extends Annotation> qualifier : qualifiers) {
				if (Primary.class == qualifier) {
					abd.setPrimary(true);
				}
				else if (Lazy.class == qualifier) {
					abd.setLazyInit(true);
				}
				else {
					abd.addQualifier(new AutowireCandidateQualifier(qualifier));
				}
			}
		}
		//有没有给BeanDefinition的回调，有就加上
		if (customizers != null) {
			for (BeanDefinitionCustomizer customizer : customizers) {
				customizer.customize(abd);
			}
		}
		//注册配置类
		BeanDefinitionHolder definitionHolder = new BeanDefinitionHolder(abd, beanName);
		definitionHolder = AnnotationConfigUtils.applyScopedProxyMode(scopeMetadata, definitionHolder, this.registry);
		BeanDefinitionReaderUtils.registerBeanDefinition(definitionHolder, this.registry);
	}