Spring 使用构造器装载属性

素颜马尾好姑娘i 2022-08-04 05:09 126阅读 0赞

1.在javaBean中将属性通过构造器传入：

private PersonDao  personDao;
    	private String name;
    	
    	public PersonServiceBean(PersonDao personDao, String name) {
    		this.personDao = personDao;
    		this.name = name;
    	}

2.在bean.xml文件中配置，从而注入值

index="0"表示构造器中的第一个参数，如果是引用的话使用ref,如果是基本类型直接使用value来设值。

3.重写dao的save方法

@Override
    public void save() {
        personDao.add();
        System.out.println(name);
    }

4.单元测试

/**
     * 构造器注入测试
     */
    @Test
    public void instanceSpring6() {
    	AbstractApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");
    	PersonService personService = (PersonService)ctx.getBean("personService");
    	personService.save();
    }

5.测试结果

九月 01, 2015 9:39:26 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
    信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@14d0ba03: display name [org.springframework.context.support.ClassPathXmlApplicationContext@14d0ba03]; startup date [Tue Sep 01 21:39:26 CST 2015]; root of context hierarchy
    九月 01, 2015 9:39:26 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
    信息: Loading XML bean definitions from class path resource [beans.xml]
    九月 01, 2015 9:39:27 下午 org.springframework.context.support.AbstractApplicationContext obtainFreshBeanFactory
    信息: Bean factory for application context [org.springframework.context.support.ClassPathXmlApplicationContext@14d0ba03]: org.springframework.beans.factory.support.DefaultListableBeanFactory@547e045
    九月 01, 2015 9:39:27 下午 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
    信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@547e045: defining beans [personDao,personService]; root of factory hierarchy
    执行PersonDaoBean中的add()方法.
    test by lic.