深入理解Spring动态依赖注入：使用Bean Scope处理可变对象

import org.openqa.selenium.WebDriver;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;
import org.springframework.context.annotation.ScopedProxyMode;

// 模拟WebDriver类，实际项目中会使用Selenium的WebDriver实现
import java.util.Collections;
import java.util.List;
import java.util.Set;
import org.openqa.selenium.By;
import org.openqa.selenium.WebElement;

@Configuration
public class AppConfig {

    // 假设您有一个DriverManager类来管理WebDriver的创建和生命周期
    // 这里的getOrCreateWebDriver()方法会根据内部状态返回现有或新建的WebDriver实例
    // 注意：DriverManager本身可以是一个Spring Bean，这里为简化示例直接实例化
    private final DriverManager driverManager = new DriverManager(); 

    @Bean
    @Scope(value = ConfigurableBeanFactory.SCOPE_PROTOTYPE, proxyMode = ScopedProxyMode.TARGET_CLASS)
    public WebDriver webDriver() {
        // 每次请求此Bean时，都会调用webDriver()方法，
        // 从而通过DriverManager获取到当前最新或新创建的WebDriver实例。
        return driverManager.getWebDriver();
    }

    // 示例：DriverManager类，负责WebDriver的生命周期管理
    public static class DriverManager {
        private WebDriver currentWebDriver; // 存储当前的WebDriver实例

        public WebDriver getWebDriver() {
            if (currentWebDriver == null || isWebDriverClosed(currentWebDriver)) {
                System.out.println("[DriverManager] Creating new WebDriver instance...");
                // 实际项目中这里会根据配置创建WebDriver，例如 new ChromeDriver()
                currentWebDriver = createNewWebDriverInstance();
            } else {
                System.out.println("[DriverManager] Returning existing WebDriver instance...");
            }
            return currentWebDriver;
        }

        private boolean isWebDriverClosed(WebDriver driver) {
            // 检查WebDriver是否已关闭或失效
            try {
                // 尝试执行一个操作，如果WebDriver已关闭会抛出异常
                // 注意：对于真实的WebDriver，这个检查可能需要更健壮的方式
                driver.getCurrentUrl(); 
                return false;
            } catch (Exception e) {
                System.out.println("[DriverManager] Detected WebDriver is closed/invalid.");
                return true;
            }
        }

        private WebDriver createNewWebDriverInstance() {
            // 实际的WebDriver创建逻辑，例如：
            // WebDriverManager.chromedriver().setup();
            // return new ChromeDriver();
            // 这里为了示例简化，返回一个模拟的WebDriver
            return new MockWebDriver("MockDriver-" + System.nanoTime());
        }

        // 模拟WebDriver类，用于演示
        private static class MockWebDriver implements WebDriver {
            private final String id;
            private boolean closed = false;

            public MockWebDriver(String id) {
                this.id = id;
                System.out.println("MockWebDriver " + id + " created.");
            }

            @Override public void get(String url) { /* ... */ }
            @Override public String getCurrentUrl() {
                if (closed) throw new IllegalStateException("WebDriver " + id + " is closed.");
                return "http://example.com/" + id;
            }
            @Override public String getTitle() { return "Mock Title"; }
            @Override public List<WebElement> findElements(By by) { return Collections.emptyList(); }
            @Override public WebElement findElement(By by) { return null; }
            @Override public String getPageSource() { return ""; }
            @Override public void close() {
                System.out.println("MockWebDriver " + id + " closed.");
                closed = true;
            }
            @Override public void quit() {
                System.out.println("MockWebDriver " + id + "