spring笔记-BeanDefinition

BeanDefinition类图继承关系

1.RootBeanDefinition

    @Test
    public void test2()
    {
        AnnotationConfigApplicationContext applicationContext=new AnnotationConfigApplicationContext();

        RootBeanDefinition item=new RootBeanDefinition();
        item.setBeanClass(TestBean.class);
        item.getPropertyValues().add("name","test");
        applicationContext.registerBeanDefinition("item",item);
        
        applicationContext.refresh();
        TestBean bean= (TestBean) applicationContext.getBean("item");
    }

输出结果:

2. ChildBeanDefinition

可以继承RootBeanDefinition的数据

    @Test
    public void test21()
    {

        AnnotationConfigApplicationContext applicationContext=new AnnotationConfigApplicationContext();

        {
            RootBeanDefinition item=new RootBeanDefinition();
            item.setBeanClass(TestBean.class);
            item.getPropertyValues().add("name","test");
            applicationContext.registerBeanDefinition("item",item);
        }

        {
            ChildBeanDefinition item2=new ChildBeanDefinition("item");
            item2.setBeanClass(SubTestBean.class);
            item2.getPropertyValues().add("text","text");
            applicationContext.registerBeanDefinition("item2",item2);
        }
        applicationContext.refresh();

        TestBean bean= (TestBean) applicationContext.getBean("item");
        SubTestBean bean2= (SubTestBean) applicationContext.getBean("item2");
    }

输出结果:

3.GenericBeanDefinition

RootBeanDefinition和ChildBeanDefinition可以用GenericBeanDefinition来代替,效果相同

    @Test
    public void test211()
    {

        AnnotationConfigApplicationContext applicationContext=new AnnotationConfigApplicationContext();

        {
            GenericBeanDefinition item=new GenericBeanDefinition();
            item.setBeanClass(TestBean.class);
            item.getPropertyValues().add("name","test");
            applicationContext.registerBeanDefinition("item",item);
        }

        {
            GenericBeanDefinition item2=new GenericBeanDefinition();
            item2.setParentName("item");
            item2.setBeanClass(SubTestBean.class);
            item2.getPropertyValues().add("text","text");
            applicationContext.registerBeanDefinition("item2",item2);
        }

        applicationContext.refresh();

        TestBean bean= (TestBean) applicationContext.getBean("item");
        SubTestBean bean2= (SubTestBean) applicationContext.getBean("item2");
    }

使用xml加载的bean也是由GenericBeanDefinition来创建

    @Test
    public void test3()
    {
        ClassPathXmlApplicationContext applicationContext=new ClassPathXmlApplicationContext(ClassUtils.addResourcePathToPackagePath(BeanDefinitionTest.class,"beanDefinition.xml"));
        TestBean bean= (TestBean) applicationContext.getBean("item");

        BeanDefinition beanDefinition=applicationContext.getBeanFactory().getBeanDefinition("item");
    }

4.AnnotatedGenericBeanDefinition

以@Configuration注解标记的会解析为AnnotatedGenericBeanDefinition

5.ConfigurationClassBeanDefinition

以@Bean注解标记的会解析为ConfigurationClassBeanDefinition

6.ScannedGenericBeanDefinition

以@Component注解标记的会解析为ScannedGenericBeanDefinition

7.BeanDefinitionBuilder

可以使用BeanDefinitionBuilder来构建BeanDefinition

public class BeanDefinitionBuilderTests {

    @Test
    public void beanClassWithSimpleProperty() {
        String[] dependsOn = new String[] { "A", "B", "C" };
        BeanDefinitionBuilder bdb = BeanDefinitionBuilder.rootBeanDefinition(TestBean.class);
        bdb.setScope(BeanDefinition.SCOPE_PROTOTYPE);
        bdb.addPropertyReference("age", "15");
        for (int i = 0; i < dependsOn.length; i++) {
            bdb.addDependsOn(dependsOn[i]);
        }

        RootBeanDefinition rbd = (RootBeanDefinition) bdb.getBeanDefinition();
    }
}

参考:
http://blog.51cto.com/dba10g/1728512