OSGi and friends methods

Developing OSGi tests can be definitely boring. First, testing is generally not a very exciting experience, but imagine if you have to handle all the OSGi issues in your tests... Don't worry junit4osgi provides methods allowing to interact easily with OSGi!

OSGi methods

junit4osgi test case extends the OSGiTestCase class. This class provides useful methods allowing to find services, get them, get the PackageAdmin service... The description of these methods can be found afterward.

The most part of the methods are available statically and non-statically. Static methods require a Bundle. Non static methods use the current bundle context, and track get services to release them when the test is done. So, we advise you to use the non-static methods. Static methods just allow you to check that a specific bundle can access to services / resources.

Service interaction

• boolean isServiceAvailable(String svc) : returns true if the service svc is available.
• boolean isServiceAvailableByPID(String itf, String pid) : return true if the service svc is available and exposed with pid as service.pid.

• ServiceReference getServiceReference(String itf): returns a service reference exposing the itf service specification, or null if not available.
• ServiceReference getServiceReference(String itf, String filter): returns a service reference matching with the \<service interface, filter\> request, or null is not available.
• ServiceReference getServiceReferenceByPID(String itf, String pid): returns a service reference exposing the service itf and exposed with a service.pid equals to pid, or null if not available.
• ServiceReference[] getServiceReferences(String itf, String filter): returns all the service references matching with the \<service interface, filter\> request, or an empty array is not available.

• Object getServiceObject(String itf, String filter): returns a service object matching with the \<service interface, filter\> request or null is not available.
• Object getServiceObject(ServiceReference ref): returns the service object associated with the given service reference or null if not available.
• Object[] getServiceObjects(String itf, String filter): gets all the service objects matching with the \<service interface, filter\> request or an empty array is no providers are available.

• void waitForService(String itf, String filter, long timeout): waits for a service arrival matching with the \<service interface, filter\> request. If the timeout expires, this method fails.

Get the bundle context

• BundleContext getContext() : gives access to the OSGiTestCase bundle context.

Install/Start/Uninstall bundles

• Bundle installBundle(String url): installs a bundle from the given url. This method fails if the bundle cannot be installed.
• Bundle installBundle(String url, InputStream stream): installs a bundle from the given input stream. This methods fails if the bundle cannot be installed.
• Bundle installAndStart(String url): installs a bundle from the given url and starts it. This methods fails if the bundle cannot be installed and started correctly.
• Bundle installAndStart(String url, InputStream stream): installs a bundle from the given input stream and starts it. This methods fails if the bundle cannot be installed and started correctly.
• Bundle getBundle(long bundleId): gets an installed bundle by its bundle id, or null if not found.
• Bundle getBundle(String name): gets an installed bundle by its symbolic name. Fails if not found.

PackageAdmin

• PackageAdmin getPackageAdmin(): gives access to the Package Admin service exposed by the framework.
• refresh(): refresh package wires.

Extensibility: Helper objects

junit4osgi provides an extensibility mechanism to reduce the pain of testing. So, if you're interacting with specific services or environment, you can use Helper objects. Those object have to be created in the setUp method and disposed in the tearDown method.

So, for example, if you write iPOJO tests, you can use the iPOJO helper providing a lot of utility functions simplifying the development of tests.

public class MyTest extends OSGiTestCase {
	ComponentInstance fooProvider1, fooProvider2;
	
	IPOJOHelper helper; // Helper object

    public void setUp() {
        helper = new IPOJOHelper(this);	// Create the object.	
	String type2 = "PS-FooProviderType";
	
	fooProvider1 = helper.createComponentInstance(type2, p3);
        fooProvider2 = helper.createComponentInstance(type2, "FooProvider-4");
    }
	
    public void tearDown() {
	helper.dispose(); // Dispose it, instances will be disposed too.
    }

You can also implements your own helper (for specific purpose) by just implementing the Helper interface.