Spring自定義註釋：如何繼承屬性？

Question

我創建自己的自定義快捷方式的註釋，如Spring Documentation描述：

@Target({ElementType.METHOD, ElementType.TYPE}) 
@Retention(RetentionPolicy.RUNTIME) 
@Transactional(value = "Custom", readOnly = true) 
public @interface CustomTransactional { 
} 

是否有可能，這與我的自定義註釋我可能還可以設置任何其他屬性，這是在@Transactional可用？我希望能夠用我的註釋，例如，像這樣：

@CustomTransactional(propagation = Propagation.REQUIRED) 
public class MyClass { 

} 

Answer 1

不，這是行不通的，如果你想將必須對您的自定義註釋本身這種方式設置附加屬性：

@Target({ElementType.METHOD, ElementType.TYPE}) 
@Retention(RetentionPolicy.RUNTIME) 
@Transactional(value = "Custom", readOnly = true, propagation = Propagation.REQUIRED) 
public @interface CustomTransactional { 
} 

溶液（壞的:-)）可以定義與基本集合您爲您的方案見例多發性註釋：

@Target({ElementType.METHOD, ElementType.TYPE}) 
@Retention(RetentionPolicy.RUNTIME) 
@Transactional(value = "Custom", readOnly = true, propagation = Propagation.REQUIRED) 
public @interface CustomTransactionalWithRequired { 
} 

@Target({ElementType.METHOD, ElementType.TYPE}) 
@Retention(RetentionPolicy.RUNTIME) 
@Transactional(value = "Custom", readOnly = true, propagation = Propagation.SUPPORTED) 
public @interface CustomTransactionalWithSupported { 
} 

Answer 2

在（至少）春季4，你可以這樣做指定元件的註釋內，例如：

@Target({ElementType.METHOD, ElementType.TYPE}) 
@Retention(RetentionPolicy.RUNTIME) 
@Transactional(value = "Custom", readOnly = true) 
public @interface CustomTransactional { 
    Propagation propagation() default Propagation.SUPPORTED; 
} 

來源：http://docs.spring.io/spring/docs/current/spring-framework-reference/html/beans.html#beans-meta-annotations