spring bean初始化过程

public static void main(String[] args) {
       ApplicationContext context =                new AnnotationConfigApplicationContext(Application.class);
       MessagePrinter printer = context.getBean(MessagePrinter.class);
       printer.printMessage();
   }

public AnnotationConfigApplicationContext() {		this.reader = new AnnotatedBeanDefinitionReader(this);		this.scanner = new ClassPathBeanDefinitionScanner(this);
}public AnnotationConfigApplicationContext(Class<?>... annotatedClasses) {   		this();   		register(annotatedClasses);
  		refresh();
  	}

public void register(Class<?>... annotatedClasses) {
Assert.notEmpty(annotatedClasses, "At least one annotated class must be specified");		this.reader.register(annotatedClasses);
}

public void scan(String... basePackages) {		Assert.notEmpty(basePackages, "At least one base package must be specified");
this.scanner.scan(basePackages);	}

public void register(Class<?>... annotatedClasses) {
for (Class<?> annotatedClass : annotatedClasses) {
registerBean(annotatedClass);
}
}