IoC

BeanFactory (Spring Framework 6.0.13 API)

@Component
@Scope(
    value="prototype",
//    proxyMode=ScopedProxyMode.DEFAULT
//    proxyMode=ScopedProxyMode.INTERFACES
    /* cglib 의 dynamic proxy 가 적용
     * proxy 를 거쳐서 참조하도록 함.
     * jdk 의 dynamic proxy 는 interface 기반인데
     * cglib 는 class 도 proxy 가 가능하게 해준다.
     * 위의 interfaces 를 사용하면 jdk 기반의 proxy 를 사용
     */
    proxyMode=ScopedProxyMode.TARGET_CLASS
)
public class Proto  {
}

@Component
public class Single {
	@Autowired
	private Proto proto;
	public Proto getProto() {
		return this.proto;
	}
}

//Single class 가 singleton 이더라도 proto

EnvironmentCapable (Spring Framework 6.0.13 API)

두가지 기능 1. Profile : 환경, 빈들의 집합 2. Properties : key-vaule 쌍에 접근, 계층형

vm option -Dspring.profiles.active=test

@Configuration
@Profile("test")
public class TestConfiguration {
	@Bean
	//@Profile("test") //이렇게 해도
	public BookRepository bookRepository() {
		return new TestBookRepository();
	}
}

/* test 프로파일은 안줘도 되는건 기분탓..? */

vm option -Dapp.name=Spring5

MainApp.java

package herdin.boot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.PropertySource;

@SpringBootApplication
@PropertySource("classpath:/app.properties")
public class MainApp {
	@Autowired
	ApplicationContext ctx;
	
	public static void main(String[] args) {
		SpringApplication.run(MainApp.class);
	}
}

AppRunner.java

package herdin.boot;

import java.util.Arrays;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.context.ApplicationContext;
import org.springframework.core.env.Environment;
import org.springframework.stereotype.Component;

@Component
public class AppRunner implements ApplicationRunner {
	@Autowired
	ApplicationContext ctx;
	
	@Override
	public void run(ApplicationArguments args) throws Exception {
		Environment environment = ctx.getEnvironment();
		System.out.println(Arrays.deepToString(environment.getDefaultProfiles()));
		System.out.println(environment.getProperty("app.name"));
		System.out.println(environment.getProperty("app.about"));
	}
}

app.properties

app.about=thisIsAbout

org.springframework.context.MessageSource

MainApp.java

package herdin.boot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.MessageSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.ReloadableResourceBundleMessageSource;

@SpringBootApplication
public class MainApp {
	
	public static void main(String[] args) {
		SpringApplication.run(MainApp.class);
	}
	
	/* MessageSource 를 다른 종류로 변경해 보았음 */
	@Bean
	public MessageSource messageSource() {
		ReloadableResourceBundleMessageSource messageSource = new ReloadableResourceBundleMessageSource();
		messageSource.setBasename("classpath:/messages");
		messageSource.setDefaultEncoding("UTF-8");
		messageSource.setCacheSeconds(3);
		return messageSource;
	}
}

AppRunner.java

package herdin.boot;

import java.util.Locale;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;

@Component
public class AppRunner implements ApplicationRunner {
	@Autowired
//	MessageSource messageSource; //이거나
	ApplicationContext messageSource; //이거나 같음
	
	@Override
	public void run(ApplicationArguments args) throws Exception {
		while(true) {
			System.out.println(messageSource.getClass());
			System.out.println(messageSource.getMessage("greeting", new String[] {"target"}, Locale.getDefault()));
			System.out.println(messageSource.getMessage("greeting", new String[] {"target"}, Locale.KOREA));
			Thread.sleep(1000L);
		}
	}
}

messages_ko_KR.properties

greeting=안녕 {0}

messages.properties

greeting=Hello {0}

ApplicationEventPublisher (Spring Framework 6.0.13 API)

Observer pattern

before Spring 4.2

AppRunner.java

package herdin.boot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.stereotype.Component;

import herdin.boot.event.MyEvent;

@Component
public class AppRunner implements ApplicationRunner {
	@Autowired
//	ApplicationContext applicationContext;
	ApplicationEventPublisher applicationEventPublisher;
	
	@Override
	public void run(ApplicationArguments args) throws Exception {
		applicationEventPublisher.publishEvent(new MyEvent(this, 1004));
	}
}

MyEventHandler.java

package herdin.boot.event;

import org.springframework.context.ApplicationListener;
import org.springframework.stereotype.Component;

@Component
public class MyEventHandler implements ApplicationListener<MyEvent> {
	@Override
	public void onApplicationEvent(MyEvent event) {
		System.out.println("EVENT RECV : " + event.getData());
	}
}

MyEvent.java

package herdin.boot.event;

import org.springframework.context.ApplicationEvent;

public class MyEvent extends ApplicationEvent {
	private int data;
	public MyEvent(Object source) {
		super(source);
	}
	public MyEvent(Object source, int data) {
		super(source);
		this.data = data;
	}
	public int getData() {
		return this.data;
	}
}

after 4.2

MyEventHandler.java

package herdin.boot.event;

import org.springframework.context.event.EventListener;
import org.springframework.stereotype.Component;

@Component
public class MyEventHandler /*implements ApplicationListener<MyEvent> 구현할 필요가 없어짐*/ {
	
	@EventListener /*Spring annotation 추가*/
	public void onApplicationEventCustom(MyEvent event) { /*함수명도 아무렇게나*/
		System.out.println("EVENT RECV : " + event.getData());
	}
}

MyEvent.java

package herdin.boot.event;

public class MyEvent /*implements ApplicationEvent 구현 할 필요가 없어짐*/ {
	private Object source;
	private int data;
	public MyEvent(Object source) {
		this.source = source;
	}
	public MyEvent(Object source, int data) {
		this.source = source;
		this.data = data;
	}
	public Object getSource() {
		return this.source;
	}
	public int getData() {
		return this.data;
	}
}

위에서 같은 이벤트를 처리하는 핸들러가 추가되면 이벤트가 발생(publish)했을때 모두 수행된다 이벤트 리스너에서 @Order(int) 로 순서 조정 가능 Ordered.HIGHEST_PRECEDENCE Ordered.LOWEST_PRECEDENCE

ResourceLoader (Spring Framework 6.0.13 API)

AppRunner.java

package herdin.boot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.core.io.ResourceLoader;
import org.springframework.stereotype.Component;

@Component
public class AppRunner implements ApplicationRunner {
	@Autowired
//	ApplicationContext resourceLoader;
	ResourceLoader resourceLoader;
	
	@Override
	public void run(ApplicationArguments args) throws Exception {
		System.out.println(resourceLoader.getResource("classpath:/messages.properties").getFile().getCanonicalPath());
		Thread.sleep(2000L);
		System.exit(0);
	}
}