Using Service Builder in Modular Liferay Projects (OSGi Modules)

Service Builder is one of the most powerful tools provided by Liferay for generating database interaction layers. In modular OSGi-based Liferay projects, it allows you to define entities and auto-generate service layers that are ready for use across modules.

🧰 Prerequisites

• Liferay 7.x or Liferay DXP workspace
• Blade CLI installed
• Basic understanding of OSGi modular structure

📦 Step 1: Create Service Builder Module

blade create -t service-builder -p com.example.sb -c Product product-sb

This creates 3 modules:

• product-sb-api – Interface layer
• product-sb-service – Implementation layer
• product-sb – Portlet or UI module (optional)

📝 Step 2: Define Entity in service.xml

Edit product-sb-service/src/main/resources/META-INF/service.xml

<?xml version="1.0"?>
<service-builder package-path="com.example.sb">

  <author>YourName</author>

  <namespace>SB</namespace>

  <entity name="Product" local-service="true" remote-service="false">
    <column name="productId" type="long" primary="true" />
    <column name="name" type="String" />
    <column name="price" type="double" />
  </entity>

</service-builder>

⚙️ Step 3: Build Services

./gradlew buildService

This will generate:

• Persistence layer
• Local service interfaces and implementations
• ServiceUtil classes for easy access

🔌 Step 4: Use the Generated Services

In any other OSGi module, include a dependency on the API module:

dependencies {
    compileOnly project(":modules:product-sb:product-sb-api")
}

Inject the local service using OSGi annotations:

@Reference
private ProductLocalService productLocalService;

Then you can use the service like this:

Product product = productLocalService.createProduct(counterLocalService.increment());
product.setName("Phone");
product.setPrice(499.99);
productLocalService.addProduct(product);

🚀 Step 5: Deploy and Test

Deploy all the modules using:

./gradlew deploy

Use Gogo shell or custom portlet to test service calls.

🧪 Example Gogo Shell Test

:load com.example.sb.service.ProductLocalService
productLocalService.getProducts(0, 10)

📘 Summary

• Service Builder works well in modular OSGi Liferay projects.
• You can generate entities and services with a simple XML.
• Split code into clean layers: API and SERVICE.
• Can be consumed from any OSGi portlet or module.

🔗 Useful Resources

• Liferay Learn
• Blade CLI Samples