Creating Service Wrappers

With Service Wrappers, you can override default service methods to add extra functionality. For example, you may want the value of a field you’ve added to Liferay’s User object to be saved whenever the Liferay API’s addUser or updateUser methods are called. Liferay’s service wrappers provide easy-to-use extension points for customizing Liferay’s services.

Deploying a Service Wrapper

Start a new Liferay instance by running

docker run -it -m 8g -p 8080:8080 liferay/portal:7.4.3.120-ga120

Sign in to Liferay at http://localhost:8080. Use the email address [e-mail] and the password test. When prompted, change the password to learn.

Then, follow these steps to deploy the example:

1. Download and unzip the liferay-j1c2.zip example project.

   curl https://resources.learn.liferay.com/dxp/latest/en/liferay-development/liferay-internals/extending-liferay/liferay-j1c2.zip -O
   

   unzip liferay-j1c2.zip
   

2. Build and deploy the project module.

   cd liferay-j1c2
   

   ./gradlew deploy -Ddeploy.docker.container.id=$(docker ps -lq)
   

   Note

   This command is the same as copying the deployed jars to /opt/liferay/osgi/modules on the Docker container.

3. Confirm the deployment in the Liferay Docker container console.

   STARTED com.acme.j1c2.impl_1.0.0 [1439]
   

4. To verify the example module’s customization, open your browser to https://localhost:8080.

5. Log out of Liferay and log back in. The service wrapper prints this message to the Liferay Docker container console:

   INFO  [http-nio-8080-exec-6][J1C2UserLocalServiceWrapper:25] Invoking #authenticateByEmailAddress(long, String, String, Map, Map, Map)
   

This example prints a message to the console whenever the authenticateByEmailAddress method is called.

Creating a Service Wrapper Class

1. Choose the service you want to wrap. This example creates a service wrapper for UserLocalService, so it extends UserLocalServiceWrapper:

public class J1C2UserLocalServiceWrapper extends UserLocalServiceWrapper {

1. Annotate the class so Liferay knows this is a service wrapper component.

@Component(service = ServiceWrapper.class)

1. Choose the method you want to override and add your own implementation.

@Override
public int authenticateByEmailAddress(
		long companyId, String emailAddress, String password,
		Map<String, String[]> headerMap, Map<String, String[]> parameterMap,
		Map<String, Object> resultsMap)
	throws PortalException {

	if (_log.isInfoEnabled()) {
		_log.info(
			"Invoking #authenticateByEmailAddress(long, String, String, " +
				"Map, Map, Map)");
	}

	return super.authenticateByEmailAddress(
		companyId, emailAddress, password, headerMap, parameterMap,
		resultsMap);
}

Overriding a Method

1. Open the J1C2UserLocalServiceWrapper class in your text editor or IDE.

2. Inside the class, create a public method called getUser. This overrides UserLocalService’s getUser method. As such, it must pass a long as an argument and return a User. This method should also throw a PortalException. Make sure to add the @Override annotation.

   @Override
   public User getUser(long userId) throws PortalException {
   }
   

3. Since this method returns the User object, import it at the top of the file.

   import com.liferay.portal.kernel.model.User;
   

4. Create a similar method to the one in the example so that every time the getUser method is called, it prints a message to the console.

   if (_log.isInfoEnabled()) {
       _log.info(
           "Invoking #getUser(long)");
   }
   

5. You still want getUser to be called, so make the method return the results of calling getUser’s super method.

   return super.getUser(userId);
   

6. In the end, your method should look like this:

   @Override
   public User getUser(long userId) throws PortalException {
       if (_log.isInfoEnabled()) {
           _log.info(
               "Invoking #getUser(long)");
       }
   
       return super.getUser(userId);
   }
   

7. Build and deploy your module.

   ./gradlew build deploy -Ddeploy.docker.container.id=$(docker ps -lq)
   

Testing Your Service Wrapper

1. Go back to https://localhost:8080.

2. Click My Profile in the User menu. This takes you to your profile page.

3. When you open your profile page, Liferay calls the getUser method a couple times. Check your console for the following message:

INFO  [http-nio-8080-exec-4][J1C2UserLocalServiceWrapper:39] Invoking #getUser(long)

Congratulations! You’ve customized a service’s methods using a Liferay service wrapper.

Related Topics

• Using an OSGi Service
• Using Job Scheduler
• Users