User-Defined Services

User-defined services (UDS) allow you to wrap reusable logic into a service that can be used by other Vault Java SDK code, such as triggers, actions, or user-defined classes. Much like Vault Java SDK services, UDS are stateless singletons whose methods, once exited, return their allocated memory to the maximum memory execution limit: only the method parameters and return value counts toward the memory limit. Since UDS are stateless, nothing is retained beyond the service method execution.

UDS only execute by calls from other classes, differentiating them from Vault extensions that execute when a user or the system initiates an operation.

Locate the user-defined service using ServiceLocator, just like Vault Java SDK services. Once located, execute the service with a normal Java method call.

User-Defined Services vs. User-Defined Classes

Unlike user-defined classes, the memory UDS use in their methods is freed up when the method exits. Only the method return value counts towards the total SDK extension memory limit. However, it is important to note that just like SDK services, UDS do not store any data after the method exits. If data needs to be stored, or if common methods need to be shared between triggers or actions, a user-defined class should be used.

Using User-Defined Services

To use a UDS, extend UserDefinedService and create a class implementing the UserDefinedService extension. The following examples illustrate how to perform a product search with a UDS.

Create a new service by extending UserDefinedService and using the @UserDefinedServiceInfo annotation.

@UserDefinedServiceInfo
public interface ProductSearchClass extends UserDefinedService {
    boolean doesProductExist();
}

Implement the new interface that includes reusable code.

@UserDefinedServiceInfo
public class ProductSearchClassImpl implements ProductSearchClass {
    @Override
    public boolean doesProductExist() {
        // Reusable code
        return true;
    }
}

Locate the service and execute method from a Vault extension such as a trigger or an action.

ProductSearchClass productSearchClass = ServiceLocator.locate(ProductSearchClass.class);
boolean productExists = productSearchClass.doesProductExist();

Debugging User-Defined Services

When the SDK debugger is attached to a Vault session, the UDS executes on the client side, just like a user-defined class. Therefore, for any SDK invocations the service makes, the size of the objects returned by the invocations counts towards memory usage. The memory used by those objects is not decremented when the service method exits.

Objects returned by the service method do not count towards the Vault extension memory limit when the SDK debugger is attached to a Vault session.