#############################Configuration使用示例######################################################
/**
 * 1、配置類里面使用@Bean標(biāo)注在方法上給容器注冊(cè)組件，默認(rèn)也是單實(shí)例的
 * 2、配置類本身也是組件
 * 3、proxyBeanMethods：代理bean的方法
 *      Full(proxyBeanMethods = true)、【保證每個(gè)@Bean方法被調(diào)用多少次返回的組件都是單實(shí)例的】
 *      Lite(proxyBeanMethods = false)【每個(gè)@Bean方法被調(diào)用多少次返回的組件都是新創(chuàng)建的】
 *      組件依賴必須使用Full模式默認(rèn)。其他默認(rèn)是否Lite模式
 *
 *
 *
 */
@Configuration(proxyBeanMethods = false) //告訴SpringBoot這是一個(gè)配置類 == 配置文件
public class MyConfig {
    /**
     * Full:外部無論對(duì)配置類中的這個(gè)組件注冊(cè)方法調(diào)用多少次獲取的都是之前注冊(cè)容器中的單實(shí)例對(duì)象
     * @return
     */
    @Bean //給容器中添加組件。以方法名作為組件的id。返回類型就是組件類型。返回的值，就是組件在容器中的實(shí)例
    public User user01(){
        User zhangsan = new User("zhangsan", 18);
        //user組件依賴了Pet組件
        zhangsan.setPet(tomcatPet());
        return zhangsan;
    }
    @Bean("tom")
    public Pet tomcatPet(){
        return new Pet("tomcat");
    }
}
################################@Configuration測(cè)試代碼如下########################################
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan("com.atguigu.boot")
public class MainApplication {
    public static void main(String[] args) {
        //1、返回我們IOC容器
        ConfigurableApplicationContext run = SpringApplication.run(MainApplication.class, args);
 
        //2、查看容器里面的組件
        String[] names = run.getBeanDefinitionNames();
        for (String name : names) {
            System.out.println(name);
        }
        //3、從容器中獲取組件
        Pet tom01 = run.getBean("tom", Pet.class);
        Pet tom02 = run.getBean("tom", Pet.class);
        System.out.println("組件："+(tom01 == tom02));

        //4、com.atguigu.boot.config.MyConfig$$EnhancerBySpringCGLIB$$51f1e1ca@1654a892
        MyConfig bean = run.getBean(MyConfig.class);
        System.out.println(bean);
 
        //如果@Configuration(proxyBeanMethods = true)代理對(duì)象調(diào)用方法。SpringBoot總會(huì)檢查這個(gè)組件是否在容器中有。
        //保持組件單實(shí)例
        User user = bean.user01();
        User user1 = bean.user01();
        System.out.println(user == user1);
        User user01 = run.getBean("user01", User.class);
        Pet tom = run.getBean("tom", Pet.class);
        System.out.println("用戶的寵物："+(user01.getPet() == tom));

    }
}

 * 4、@Import({User.class, DBHelper.class})
 *      給容器中自動(dòng)創(chuàng)建出這兩個(gè)類型的組件、默認(rèn)組件的名字就是全類名
 *
 *
 *
 */
@Import({User.class, DBHelper.class})
@Configuration(proxyBeanMethods = false) //告訴SpringBoot這是一個(gè)配置類 == 配置文件
public class MyConfig {
}

=====================測(cè)試條件裝配==========================
@Configuration(proxyBeanMethods = false) //告訴SpringBoot這是一個(gè)配置類 == 配置文件
//@ConditionalOnBean(name = "tom")
@ConditionalOnMissingBean(name = "tom")
public class MyConfig {
    /**
     * Full:外部無論對(duì)配置類中的這個(gè)組件注冊(cè)方法調(diào)用多少次獲取的都是之前注冊(cè)容器中的單實(shí)例對(duì)象
     * @return
     */
    @Bean //給容器中添加組件。以方法名作為組件的id。返回類型就是組件類型。返回的值，就是組件在容器中的實(shí)例
    public User user01(){
        User zhangsan = new User("zhangsan", 18);
        //user組件依賴了Pet組件
        zhangsan.setPet(tomcatPet());
        return zhangsan;
    }
 
    @Bean("tom22")
    public Pet tomcatPet(){
        return new Pet("tomcat");
    }
}
public static void main(String[] args) {
        //1、返回我們IOC容器
        ConfigurableApplicationContext run = SpringApplication.run(MainApplication.class, args);
 
        //2、查看容器里面的組件
        String[] names = run.getBeanDefinitionNames();
        for (String name : names) {
            System.out.println(name);
        }
        boolean tom = run.containsBean("tom");
        System.out.println("容器中Tom組件："+tom);
        boolean user01 = run.containsBean("user01");
        System.out.println("容器中user01組件："+user01);
        boolean tom22 = run.containsBean("tom22");
        System.out.println("容器中tom22組件："+tom22);
    }

======================beans.xml=========================
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
 
    <bean id="haha" class="com.atguigu.boot.bean.User">
        <property name="name" value="zhangsan"></property>
        <property name="age" value="18"></property>
    </bean>
 
    <bean id="hehe" class="com.atguigu.boot.bean.Pet">
        <property name="name" value="tomcat"></property>
    </bean>
</beans>

@ImportResource("classpath:beans.xml")
public class MyConfig {}
 
======================測(cè)試=================
        boolean haha = run.containsBean("haha");
        boolean hehe = run.containsBean("hehe");
        System.out.println("haha："+haha);//true
        System.out.println("hehe："+hehe);//true

public class getProperties {
     public static void main(String[] args) throws FileNotFoundException, IOException {
         Properties pps = new Properties();
         pps.load(new FileInputStream("a.properties"));
         Enumeration enum1 = pps.propertyNames();//得到配置文件的名字
         while(enum1.hasMoreElements()) {
             String strKey = (String) enum1.nextElement();
             String strValue = pps.getProperty(strKey);
             System.out.println(strKey + "=" + strValue);
             //封裝到JavaBean。
         }
     }
 }

/**
 * 只有在容器中的組件，才會(huì)擁有SpringBoot提供的強(qiáng)大功能
 */
@Component
@ConfigurationProperties(prefix = "mycar")
public class Car {
    private String brand;
    private Integer price;
 
    public String getBrand() {
        return brand;
    }
    public void setBrand(String brand) {
        this.brand = brand;
    }
    public Integer getPrice() {
        return price;
    }
    public void setPrice(Integer price) {
        this.price = price;
    }
    @Override
    public String toString() {
        return "Car{" +
                "brand='" + brand + '\'' +
                ", price=" + price +
                '}';
    }
}

@Import(AutoConfigurationPackages.Registrar.class) ?//給容器中導(dǎo)入一個(gè)組件
public @interface AutoConfigurationPackage {}

//利用Registrar給容器中導(dǎo)入一系列組件
//將指定的一個(gè)包下的所有組件導(dǎo)入進(jìn)來，MainApplication 所在包下。