如何使用@import导入实现了ImportBeanDefinitionRegistrar接口的类？

如何使用@import导入实现了ImportBeanDefinitionRegistrar接口的类？

 

在程序开发的时候，我们经常会遇见一个名词“接口”这也是我们做开发人员工作中必不可少的一个技术，接下来就和大家分享一下怎么使用@import导入实现了ImportBeanDefinitionRegistrar接口的类。

 

package com.example.demo9;

import com.example.demo9.server.MyServer;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.context.ConfigurableApplicationContext;

import java.util.Arrays;

@SpringBootApplication

public class Demo9Application {

    public static void main(String[] args) {

        ConfigurableApplicationContext context = SpringApplication.run(Demo9Application.class, args);

        String[] beanNamesForType = context.getBeanNamesForType(MyServer.class);

        System.out.println(Arrays.asList(beanNamesForType).toString());

        context.close();

    }

}

public interface MyServer {

    void fun();

}

package com.example.demo9.server;

//这里最好不要加@Service,除非有其它要求

public class MyServerAImp implements MyServer{

    @Override

    public void fun() {

        System.out.println("MyServerAImp>>>>>>>>>>>>>>");

    }

}

package com.example.demo9.server;

//这里最好不要加@Service,除非有其它要求

public class MyServerBImp implements MyServer{

    @Override

    public void fun() {

        System.out.println("MyServerBImp>>>>>>>>>>>>>>");

    }

}

package com.example.demo9.registrar;

import com.example.demo9.server.MyServerAImp;

import com.example.demo9.server.MyServerBImp;

import org.springframework.beans.factory.support.BeanDefinitionRegistry;

import org.springframework.beans.factory.support.GenericBeanDefinition;

import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;

import org.springframework.core.type.AnnotationMetadata;

public class MyImportBeanDefinitionRegistrar implements ImportBeanDefinitionRegistrar {

    @Override

    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {

        //GenericBeanDefinition对象设置BeanDefinition

        GenericBeanDefinition genericBeanDefinitionMyServerAImp=new GenericBeanDefinition();

        genericBeanDefinitionMyServerAImp.setBeanClass(MyServerAImp.class);

        GenericBeanDefinition genericBeanDefinitionMyServerBImp=new GenericBeanDefinition();

        genericBeanDefinitionMyServerBImp.setBeanClass(MyServerBImp.class);

        //注册

        registry.registerBeanDefinition("genericBeanDefinitionMyServerAImp",genericBeanDefinitionMyServerAImp);

        registry.registerBeanDefinition("genericBeanDefinitionMyServerBImp",genericBeanDefinitionMyServerBImp);

    }

}

package com.example.demo9.configuration;

import com.example.demo9.registrar.MyImportBeanDefinitionRegistrar;

import org.springframework.context.annotation.Configuration;

import org.springframework.context.annotation.Import;

@Configuration

@Import(MyImportBeanDefinitionRegistrar.class)

public class MyConfiguration {

}