Spring custom shortcut annotations with Meta-annotations

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If you find you are repeatedly using the same attributes with @Transactional on many different methods, then Spring’s meta-annotation support allows you to define custom shortcut annotations for your specific use cases.
For example, defining the following annotations:

@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Transactional("dbTransactionManager")
public @interface DbTransaction {
	@AliasFor(annotation = Transactional.class)
	Isolation isolation() default Isolation.DEFAULT;
	
	@AliasFor(annotation = Transactional.class)
	Propagation propagation() default Propagation.REQUIRED;

	@AliasFor(annotation = Transactional.class)
	int timeout() default TransactionDefinition.TIMEOUT_DEFAULT;

	@AliasFor(annotation = Transactional.class)
	boolean readOnly() default false;

	@AliasFor(annotation = Transactional.class)
	Class<? extends Throwable>[] rollbackFor() default {};

	@AliasFor(annotation = Transactional.class)
	String[] rollbackForClassName() default {};

	@AliasFor(annotation = Transactional.class)
	Class<? extends Throwable>[] noRollbackFor() default {};

	@AliasFor(annotation = Transactional.class)
	String[] noRollbackForClassName() default {};
}

allows us to write the example from the previous section as

public class TransactionalService {

    @DbTransaction
    public void setSomething(String name) { ... }

    @DbTransaction(readOnly=true)
    public void readSomething() { ... }
}

As you can see meta-annotations can be combined to create composed annotations. In addition, composed annotations may optionally redeclare attributes from meta-annotations to allow user customization. This can be particularly useful when you want to only expose a subset of the meta-annotation’s attributes. For example, Spring’s @Transactional annotation hardcodes the transactionManager but still allows customization of the other attributes.

References