```
@Documented
@Retention(RUNTIME)
@Target({TYPE,ANNOTATION_TYPE})
public @interface DomainPolicy
```
A policy is used to encapsulate a varying business rule or process in a separate object. Multiple versions of the policy object represent different ways the process can be done.
This annotation can be applied to an interface to declare a domain policy. Any class implementing the annotated interface will be registered by the framework as an implementation of this policy.

When a policy interface has multiple implementations, it is necessary to differentiate them by using a different javax.inject.Qualifier annotation on each. This qualifier can then be used at the injection point to specify which implementation is required.

Considering the following policy:
```
 @DomainPolicy
  public interface SomePolicy {
     double computeSomething(String someParameter);
  }
 
```
Two different implementations can be declared as follows:
```
 @Named("variantA")
  public class SomePolicyVariantA {
     @Override
      public double computeSomething(String someParameter) {
          // implement variant A logic
      }
  }

 @Named("variantB")
  public class SomePolicyVariantB {
     @Override
      public double computeSomething(String someParameter) {
          // implement variant B logic
      }
  }
 
```
The "B variant" implementation can then be injected as follows:
```
 public class SomeClass {
     @Inject
     @Named("variantB")
      SomePolicy somePolicy;
 }
 
```

Annotation Type DomainPolicy