标签：logs color com vax 判断 autowire 角色 ext.get root
在spring环境下, ioc(控制反转 和 DI (依赖注入) 是等效的, 主要体现一种组合的松耦合思想. spring Ioc容器负责创建Bean, 并将Bean注入到所需的Bean中, 有xml, 注解, java配置, groovy配置等实现
声明bean的注解有:
@Component, 没有角色
@Controller, 为mvc的展现层
@RestController, springboot中使用, 相当于 @Controller和@ResponseBody
@Service, 为Service层
@Repositoy, 为数据交互层
使用bean的注解有:
@Autowired @Resource: JSR-250 @Inject: JSR-330
这种方式比较简单, 加个注解, spring就会根据aop注解去判断并加载到context中
TestService
package com.wenbronk.config.annotation; import org.springframework.stereotype.Service; /** * Created by wenbronk on 2017/5/12. */ @Service public class TestService { public String sayHello(String hello) { return "Hello" + hello; } }
TestController
package com.wenbronk.config.annotation; import org.springframework.stereotype.Service; import javax.annotation.Resource; /** * Created by wenbronk on 2017/5/12. */ @Service public class TestController { @Resource private TestService testService {
public String sayHello(String word) { return testService.sayHello(word); } }
Config配置, 使用@SpringBootConfiguration配置, 声明当前类为一个配置类
package com.wenbronk.config.annotation; import org.springframework.boot.SpringBootConfiguration; import org.springframework.context.annotation.ComponentScan; /** * Created by wenbronk on 2017/5/12. */ @SpringBootConfiguration @ComponentScan(value = {"com.wenbronk.config.annotation"}) public class AnnotationConfig { }
Test
package com.wenbronk.config.annotation; import org.springframework.context.annotation.AnnotationConfigApplicationContext; /** * Created by wenbronk on 2017/5/12. */ public class TestAnnotation { public static void main(String[] args) { AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(AnnotationConfig.class); TestController user = context.getBean(TestController.class); String sayHello = user.sayHello("你好"); System.out.println(sayHello); } }
关键在于config配置, 要保证使用的每个bean在config类下都有@Bean加入到context中
1), TestService, TestController,
和上面的一样, 去掉 @Service就好...
2), javaconfig, 使用@Bean标签注入到context中
package com.wenbronk.config.java; import org.springframework.boot.SpringBootConfiguration; import org.springframework.context.annotation.Bean; /** * 除了使用上面那种方法, 还可以直接new * Created by wenbronk on 2017/5/12. */ @SpringBootConfiguration public class JavaConfig2 { @Bean public FunctionService functionService() { return new FunctionService(); }
/** * spring容器中有的bean, 可以直接作为参数传入 * @param functionService * @return */ @Bean public UserFunctionService userFunctionService(FunctionService functionService) { UserFunctionService userFunctionService = new UserFunctionService(); userFunctionService.setFunctionService(functionService); return userFunctionService; } }
spring容器提供一个好处, 在context中管理的bean, 可通过形参的形式直接注入
3), Test
package com.wenbronk.config.java; import org.springframework.context.annotation.AnnotationConfigApplicationContext; /** * Created by root on 2017/5/12. */ public class TestJava { public static void main(String[] args ) { AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(JavaConfig2.class); TestController bean = context.getBean(TestController.class); String hello = bean.sayHello("hello"); System.out.println(hello); } }
标签：logs color com vax 判断 autowire 角色 ext.get root
原文地址：http://www.cnblogs.com/wenbronk/p/6848976.html
