IOC - 自定义IOC容器-蒲公英云

IOC - 自定义IOC容器

1、定义接口与实现类

// Service接口
public interface Service {
    void execute();
}
// Service的实现类
public class MyService implements Service {
    @Override
    public void execute() {
        System.out.println("MyService 执行了.");
    }
}

2、自定义ioc容器以绑定接口与实现类

import java.util.HashMap;
import java.util.Map;
public class IoCContainer {
    private Map<Class<?>, Object> components = new HashMap<>();
    public <T> void register(Class<T> componentClass, T component) {
        components.put(componentClass, component);
    }
    public <T> T resolve(Class<T> componentClass) {
        if (components.containsKey(componentClass)) {
            return (T) components.get(componentClass);
        } else {
            throw new RuntimeException("Component not found: " + componentClass.getName());
        }
    }
}

3.使用：

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
//@SpringBootApplication
public class DemoLfsunStudyCustomiocApplication {
//    public static void main(String[] args) {
//        SpringApplication.run(DemoLfsunStudyCustomiocApplication.class, args);
//    }
    public static void main(String[] args) {
        IoCContainer container = new IoCContainer();
        container.register(Service.class, new MyService());
        Service service = container.resolve(Service.class);
        service.execute();
    }
}