Question

我创建了一个注释，用于创建使用环境中的值填充的ThreadPoolTaskExecutors。但是，当我自动装配bean时，它给了我一个代理并调用代理上的方法给出了错误的值。

如果我手动访问目标类，那么我会得到正确的值。

Executor exec = (Executor) ((Advised) executor).getTargetSource().getTarget();
ThreadPoolTaskExecutor taskExec = (ThreadPoolTaskExecutor) exec;

我一直在摸不着头脑，为什么我会得到一个代理bean，但似乎无法弄明白。

我正在使用注释导入我的注册器类，该类实现ImportBeanDefinitionRegistrar来注册bean。注册商代码如下：

public class ExecutorEnumerationRegistrar implements ImportBeanDefinitionRegistrar, EnvironmentAware {

    public static final String CORE_POOL_SIZE = "corePoolSize";
    public static final String MAX_POOL_SIZE = "maxPoolSize";
    public static final String QUEUE_CAPACITY = "queueCapacity";
    public static final String THREAD_NAME_PREFIX = "threadNamePrefix";
    private static final String REJECTED_EXECUTION_HANDLER = "rejectedExecutionHandler";
    private static final String NAMES = "names";
    private static final String REJECTED_HANDLER = "rejectedHandler";
    private Environment env;

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
        Map<String, Object> attrs = importingClassMetadata.getAnnotationAttributes(ThreadPoolTaskExecutorCreator.class.getName(), true);
        final String[] beanNames = (String[]) attrs.get(NAMES);
        final String[] policyClass = (String[]) attrs.get(REJECTED_HANDLER);
        for (int x = 0; x < beanNames.length; x++) {
            createAndRegisterBean(beanNames[x], policyClass[x], registry);
        }
    }

    private void createAndRegisterBean(String name, String policyClass, BeanDefinitionRegistry registry) {
        GenericBeanDefinition bd = new GenericBeanDefinition();
        bd.setBeanClass(ThreadPoolTaskExecutor.class);
        bd.setAutowireCandidate(true);
        bd.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
        MutablePropertyValues mpv = bd.getPropertyValues();
        populateProperties(mpv, name, policyClass);
        registry.registerBeanDefinition(name, bd);
    }

    private void populateProperties(MutablePropertyValues mpv, String name, String policyClass) {
        mpv.add(CORE_POOL_SIZE, Integer.valueOf(env.getProperty(name + "." + CORE_POOL_SIZE)));
        mpv.add(MAX_POOL_SIZE, Integer.valueOf(env.getProperty(name + "." + MAX_POOL_SIZE)));
        mpv.add(QUEUE_CAPACITY, Integer.valueOf(env.getProperty(name + "." + QUEUE_CAPACITY)));
        try {
            mpv.add(REJECTED_EXECUTION_HANDLER, Class.forName(policyClass).newInstance());
        } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
            e.printStackTrace();
        }
        mpv.add(THREAD_NAME_PREFIX, name + "-");
    }

    @Override
    public void setEnvironment(Environment environment) {
        env = environment;
    }

}

导入注册商的注释：

@Retention(RetentionPolicy.RUNTIME)  
@Target(ElementType.TYPE) 
@Documented 
@Import(ExecutorEnumerationRegistrar.class) 
public @interface ThreadPoolTaskExecutorCreator{ 

    String[] names(); 

    String[] rejectedHandler() default ThreadPoolPolicyHandlers.CALLER_RUNS_POLICY; 

}

我已使用以下代码进行测试： Spring Boot类：

@EnableDiscoveryClient
@ComponentScan("my.test.classes")
@ThreadPoolTaskExecutorCreator(names = {"testExecutor"}, rejectedHandler = ThreadPoolPolicyHandlers.DISCARD_POLICY) 
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class, 
    SessionAutoConfiguration.class,
    DataSourceTransactionManagerAutoConfiguration.class, 
    JpaRepositoriesAutoConfiguration.class,
    JndiDataSourceAutoConfiguration.class, 
    JndiConnectionFactoryAutoConfiguration.class,
    RedisAutoConfiguration.class, RedisRepositoriesAutoConfiguration.class})
public class TestBoot {

    public static void main(String[] args) {
        SpringApplication.run(TestBoot.class, args);
    }   
}

spring-boot-starter-parent 1.4.5.RELEASE

的所有版本

我编写了一个JUnit测试，用于检查值并通过。 它唯一不起作用的是我在Spring Boot eureka应用程序中自动装配它。我有什么可以做的，它不会自动装配代理bean吗？我搜索了文档并查看了所有相关的类，但我没有看到任何与它为代理的原因有什么关系。另外，为什么在通过代理访问时会给出错误的值？

Answer 1

似乎您错过了注册ImportBeanDefinitionRegistrar实例的代码（在您的示例中为ExecutorEnumerationRegistrar）因此，有两种方法可以直接注册ImportBeanDefinitionRegistrar使用@Import注释或实现ImportSelector接口，这可以为您提供更多通用配置选项。

对于您的情况，只需在@Import({ExecutorEnumerationRegistrar.class})课程中添加Configuration即可。

@EnableDiscoveryClient
@ComponentScan("my.test.classes")
@ThreadPoolTaskExecutorCreator(names = {"testExecutor"}, rejectedHandler = ThreadPoolPolicyHandlers.DISCARD_POLICY)
// THIS IS REQUIRED
@Import({ExecutorEnumerationRegistrar.class})
// See Above
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class, 
SessionAutoConfiguration.class,
DataSourceTransactionManagerAutoConfiguration.class, 
JpaRepositoriesAutoConfiguration.class,
JndiDataSourceAutoConfiguration.class, 
JndiConnectionFactoryAutoConfiguration.class,
RedisAutoConfiguration.class, RedisRepositoriesAutoConfiguration.class})
public class TestBoot {

    public static void main(String[] args) {
        SpringApplication.run(TestBoot.class, args);
    }   
}

并且只记得在自动装配@Qualifier的实例时使用ThreadPoolTaskExecutor。参见示例组件

@Component
public class Component {

    @Autowired
    @Qualifier("testExecutor")
    private ThreadPoolTaskExecutor exec;

    // you methods
}

Spring编程bean自动作为代理而不是目标

1 个答案: