【spring】之xml和Annotation，Bean注入的方式

基于xml形式Bean注入

@Data
@AllArgsConstructor
@NoArgsConstructor
public class PersonBean {
    private Integer id;
    private String name;
    private String address;
}

<bean class="com.luna.annotation.PersonBean" id="personBean">
        <property name="name" value="张三"/>
        <property name="address" value="上海"/>
        <property name="id" value="1"/>
    </bean>

 //基于xml完成数据Bean注入
    @Test
    public void test(){
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring.xml");
        PersonBean personBean = (PersonBean) applicationContext.getBean("personBean");
        System.out.println(personBean.getAddress());
    }

基于Annotation形式Bean注入

@Configuration//告诉spring这是个配置类
public class PersonBeanConfig {

    @Bean(value = "person")//默认情况下使用方法名作为属性名
    public PersonBean personBean(){
        return new PersonBean(1,"李四","北京");
    }


}

//基于纯注解完成数据注入
    @Test
    public void test(){
        ApplicationContext applicationContext = new AnnotationConfigApplicationContext(PersonBeanConfig.class);
        PersonBean personBean = applicationContext.getBean(PersonBean.class);//类型
        System.out.println(personBean.getAddress());
        PersonBean person = (PersonBean)applicationContext.getBean("person");//属性名
        System.out.println(person.getAddress());
        String[] names= applicationContext.getBeanNamesForType(PersonBean.class);//查看在容器中当前Bean的属性名
        for(String name:names){
            System.out.println(name);
        }
    }