import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.BeanCurrentlyInCreationException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.support.StaticApplicationContext;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
import static org.junit.jupiter.api.Assertions.assertThrows;

class BeanFactoryRaceConditionTest {
    
    private final ExecutorService executorService = Executors.newFixedThreadPool(10);
    
    @Test
    void testRaceCondition() {
        StaticApplicationContext applicationContext = new StaticApplicationContext();
        applicationContext.registerSingleton("book", Book.class);

        BeanFactory beanFactory = applicationContext.getAutowireCapableBeanFactory();

        for (int i = 0; i < 10; i++) {
            executorService.execute(() -> {
                for (int j = 0; j < 1000; j++) {
                    beanFactory.getBean("book");
                }
            });
        }
        assertThrows(BeanCurrentlyInCreationException.class, () -> {
            for (int i = 0; i < 1000; i++) {
                beanFactory.getBean("book");
            }
        });
    }

    @Test
    void testNoRaceCondition() {
        ExecutorService executorService = Executors.newFixedThreadPool(10);

        DefaultListableBeanFactory beanFactory = new DefaultListableBeanFactory();
        beanFactory.registerSingleton("book", Book.class);

        for (int i = 0; i < 10; i++) {
            executorService.execute(() -> {
                for (int j = 0; j < 1000; j++) {
                    beanFactory.getBean("book");
                }
            });
        }

        assertDoesNotThrow(()->{
            for (int i = 0; i < 1000; i++) {
                beanFactory.getBean("book");
            }
        });
    }

    static class Book {
    }
}