spring4.3.8 XML文件的bean id与AutoWritingService 的属性完全不对应，也可以执行，为什么？

package BeanAutoWriting;

public class AutoWritingService {
    private AutoWritingDAO autoWritingDAO1;
    
    
    public void setAutoWritingDAO1(AutoWritingDAO autoWritingDAO) {
        System.out.println("执行set方法");
        this.autoWritingDAO1 = autoWritingDAO;
    }


    public void say(String word) {
        this.autoWritingDAO1.say(word);

    }
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd"
        default-autowire="byType" >
        
<!--id标识 class权限命名  -->         
<bean id="autoWritingService" class="BeanAutoWriting.AutoWritingService"></bean>
<bean id="autoWriting" class="BeanAutoWriting.AutoWritingDAO"></bean>

</beans>