获取所有bean的名字

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;
import org.springframework.web.context.ContextLoaderListener;
import org.springframework.web.context.WebApplicationContext;

WebApplicationContext  ac = ContextLoaderListener.getCurrentWebApplicationContext();
//ApplicationContext ac = SpringContext.getApplicationContext();
        String[] strings=ac.getBeanDefinitionNames();
        System.out.println(strings.length);

        AutowireCapableBeanFactory beanFactory = ac.getAutowireCapableBeanFactory();
        beanFactory.autowireBean(a);
        String name = a.getClass().getName();
        beanFactory.initializeBean(a, name);
        strings=ac.getBeanDefinitionNames();
        System.out.println(strings.length);
        for (String string : strings) {
            System.out.println(string);
        }