1.@Configurable

@Configurable
public class MyConfig {}

测试:

 public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyConfig.class);
        System.out.println(context.getBean(MyConfig.class));
    }

context.getBean有多种方式拿到bean，根据类class，类型等，
结果显示：容器拿到了这个bean:

2.@Bean

a.@bean注入

写个bean

public class MyBean {
}

在配置类中@Bean注入，scope配置指定单个或者多个实例方式注入

@Bean(name = "mybean")
@Scope("prototype")
 public MyBean createMyBean(){
     return new MyBean();
 }

b.通过工厂方式注入

①官方提供，实现FactoryBean方式

public class RunableFactoryBean implements FactoryBean<Jeep> {
    @Override
    public Jeep getObject() throws Exception {
        return new Jeep();
    }

    @Override
    public Class<?> getObjectType() {
        return Jeep.class;
    }

    @Override
    public boolean isSingleton() {
        return true;
    }
}

@Configurable
public class MyConfig {
    @Bean
    public RunableFactoryBean createRunnableFactoryBean(){
        return new RunableFactoryBean();
    }
}

测试，测试1：拿到工厂（用&符号前缀），测试2：拿到工厂创建的bean

public class Test1 {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyConfig.class);
        System.out.println(context.getBean("&createRunnableFactoryBean"));
        System.out.println(context.getBean(Jeep.class));
    }
}

结果打印,都拿到了:

②自定义工厂方式

public class Car {
}

public class JeepFactory {

    public Car create(){
        return new Car();
    }
}

先注入工厂，在通过工厂拿到bean

@Configurable
public class MyConfig {

    @Bean
    public JeepFactory creatJeepFactory(){
        return new JeepFactory();
    }

    @Bean
    public Car createJeep(JeepFactory factory){
        return factory.create();
    }
}

测试：略

3.初始化bean前后做一些事情：

在初始化后和销毁的时候调用一些方法:

1）方式1：实现InitializingBean（初始化后触发）, DisposableBean（销毁的时候触发）

public class Cat implements InitializingBean, DisposableBean {
    public Cat() {
        System.out.println("=======init cat=========");
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("=======afterPropertiesSet=========");
    }

    @Override
    public void destroy() throws Exception {
        System.out.println("=======destroy=========");
    }
}

2）方式2：根据@Bean注解属性配置：

public class Dog {
    public void init(){
        System.out.println("init");
    }
    public void destory(){
        System.out.println("destory");
    }
}

 @Bean(initMethod="init",destroyMethod="destory")
    public Dog createDog(){
        return new Dog();
    }

3）方式3：@PostContruct

public class Animal {

    @PostConstruct
    public void inital(){
        System.out.println("------initial--------");
    }

    @PreDestroy
    public void close(){
        System.out.println("------close--------");
    }
}

4.组件注入方式

①普通组件@Component

@Component("myUser")
public class User {}

②Resposity ，常用于数据库处理bean

@Repository
public class UserDao {
}

③@Service，常用于业务处理类

@Service
public class UserService {
}

④@controller，常用于请求控制类

@Controller
public class UserController {
}

测试：

public class App {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyConfig.class, User.class, UserDao.class,
                UserService.class, UserController.class);
        System.out.println(context.getBean(UserDao.class));
        System.out.println(context.getBean(UserService.class));
        System.out.println(context.getBean(UserController.class));
        context.close();
    }
}

运行结果:

5.依赖注入装配bean的方式

① @Autowire

如果多个bean，可以用@Quitifier(“XX”）具体指定，也可使用@Primary提高bean的优先级。

@Controller
public class UserController {
    @Autowired
    private UserDao userDao;
}

@Bean(name = "mybean")
    @Primary
    public MyBean createMyBean(){
        return new MyBean();
    }

②@Resource JSR 250的方式

@Controller
public class UserController {
    @Autowired
    private UserDao userDao;
    @Resource
    private UserService userService;
}

③@Inject JSR-330的方式

需要导包，因为spring项目默认不支持。

<dependency>
            <groupId>javax.inject</groupId>
            <artifactId>javax.inject</artifactId>
            <version>1</version>
        </dependency>

import org.springframework.stereotype.Component;
import javax.inject.Inject;
@Component("myUser")
public class User {
    //JSR-330
    @Inject
    private Cat cat;

    @Override
    public String toString() {
        return "User{" +
                "cat=" + cat +
                '}';
    }
}

6.组件注入需要扫描包支持，如何扫描包?

方式1，在AnnotationConfigApplicationContext上直接写报名：

public class AnnocationClient {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext("com.springboot.demo1",
                "com.springboot.demo2");
        System.out.println(context.getBean(User.class));
        System.out.println(context.getBean(UserDao.class));
        System.out.println(context.getBean(UserController.class));
        context.close();
    }
}

方式2:扫描配置类：：

可以写个扫描配置类：

@ComponentScan(basePackages = "com.springboot.demo1", excludeFilters= @Filter(type = FilterType.ASSIGNABLE_TYPE,classes={DogConfig.class}))
@Configurable
public class AnnocationScan {
}

注意，这里可以选择排除excludeFilters，后面说明咋排除。

public class AnnocationClient2 {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(AnnocationScan.class);
//        System.out.println(context.getBean(RunableFactoryBean.class));
        System.out.println(context.getBean(User.class));
        System.out.println(context.getBean(UserDao.class));
//        System.out.println(context.getBean(Cat.class));
        System.out.println(context.getBean(UserController.class));


    }
}

配置排除的包：

点击排除的枚举类：

public enum FilterType {
    ANNOTATION, //通过注解排除
    ASSIGNABLE_TYPE, //通过指定的类排除
    ASPECTJ, //通过aspectj表达式排除
    REGEX, //通过正则表达式排除
    CUSTOM; //自定义接口，实现org.springframework.core.type.filter.TypeFilter}排除

    private FilterType() {
    }
}

上面的截图是使用的ASSIGNABLE_TYPE自定类方式。

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