OSGi - list all instances of a factory config

ConfigsLister.java

import aQute.bnd.annotation.metatype.Meta;
import com.liferay.portal.configuration.metatype.annotations.ExtendedObjectClassDefinition;
import com.liferay.portal.configuration.metatype.bnd.util.ConfigurableUtil;
import org.osgi.framework.InvalidSyntaxException;
import org.osgi.service.cm.Configuration;
import org.osgi.service.cm.ConfigurationAdmin;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;

import java.io.IOException;

@Component
class ConfigsLister {
	
	public void getConfigs() throws IOException, InvalidSyntaxException {

		String filterString = String.format(
			"(service.factoryPid=%s)", MyConfiguration.ID);

		// You can even filter even on individual properties of the config, like 'myKey',
		// to retrieve a single config (if you know its property you configured)
//		String filterString = String.format(
//			"(&(service.factoryPid=%s)(myKey=%s))",
//			MyConfiguration.ID, "XYZ");

		// retrieves all matching configs -- created for given factory from OSGi container
		Configuration[] configurations = 
			_configurationAdmin.listConfigurations(filterString);

		
		// _configurationAdmin::listConfigurations might return <null> (not empty array)
		if (configurations == null) {
			System.out.println("Sorry, no configs found with filter " + filterString);
			return;
		}
		
		for(Configuration configuration: configurations) {
			System.out.println(
				"Found config: pid: " + configuration.getPid() + "), properties: " + 
					configuration.getProperties());

			// Gives you an instance of MyConfiguration, to retrieve all your fields nicely typed
			MyConfiguration typedConfig = ConfigurableUtil.createConfigurable(
				MyConfiguration.class, configuration.getProperties());
			
			String myKey = typedConfig.myKey();

			// ...
		}
	}

	@Reference
	private ConfigurationAdmin _configurationAdmin;

	
	// A sample OSGi config type
	@ExtendedObjectClassDefinition(
		category = "todo-my-category",
		factoryInstanceLabelAttribute = "myKey",
		scope = ExtendedObjectClassDefinition.Scope.SYSTEM
	)
	@Meta.OCD(
		factory = true, id = MyConfiguration.ID,
		localization = "content/Language", name = "todo-my-config.config-name"
	)
	public interface MyConfiguration {
		String ID = "com.acme.MyConfiguration";

		@Meta.AD(
			name = "my-key", description = "my-key.description")
		String myKey();

		// ...
	}
	
}