spring注解驱动开发3-Bean名称自定义

1. 获取 bean:
   @Bean:
   ctx.getBean("person", Person.class);
   @Bean(“personJson”):
   ctx.getBean("personJson", Person.class);
2. 括号里自定义 bean 名称: 如果没有定义, 默认是办法名 (person) : @Bean(“personJson”)

    @Test
    public void testBeanName() {AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ScopeConfig.class);
        Arrays.stream(ctx.getBeanDefinitionNames()).forEach(System.out::println);

        Person p = ctx.getBean("personJson", Person.class);
        System.out.println(p);

    }

package com.niewj.config;

import com.niewj.bean.Person;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Lazy;
import org.springframework.context.annotation.Scope;

@Configuration
public class ScopeConfig {

    /**
     * singleton 单例默认是先初始化的; prototype 默认是提早初始化, 只有 getBean 才会初始化结构!
     * singleton 单例的如果想提早初始化, 能够在 @Bean 同时加注解 @Lazy
     * @return
     */
    @Scope("singleton")
    @Lazy
    @Bean("personJson")
    public Person person() {return new Person("json", 22);
    }
}