Uno/Cpp/Snippet/Instantiate a Service

[cpp] using namespace ::rtl; using namespace ::com::sun::star::lang; using namespace ::com::sun::star::uno; using namespace ::com::sun::star::io; {

   // get service manager of component context
   // ( how the context is bootstrapped, is explained below ).
   Reference < XMultiComponentFactory > rServiceManager = xContext->getServiceManager();

   // create the Pipe service
   Reference< XInterface > r = rServiceManager->createInstanceWithContext(
                 OUString::createFromAscii( "com.sun.star.io.Pipe" ), xContext );
   assert( r.is() ); // the service must exist

   // ask the XInterface-reference for the XInputStream interface
   Reference< XInputStream > rInputStream( r , UNO_QUERY );
   assert( rInputStream.is() ); // the service must support XInputStream
   
   // ask the XInterface-reference for the XOutputStream interface
   Reference< XOutputStream > rOutputStream( r , UNO_QUERY );
   assert( rOutputStream.is() ) // test service must support XOutputStream

   [.... do some calls on the references]

   // each references calls release when it is destructed.
   // The last release destroys the object.

} In the first line, an initial component context (factory context) is bootstrapped (see below , how this can be done). The second line retrieves the bootstrapped service manager of the context. The next line creates the service com.sun.star.io.Pipe and returns a reference to XInterface (Note: the operator ->() simply returns the unacquired interface pointer). This service supports XInputStream and XOutputStream , the next lines retrieve these interfaces. The used reference constructor (the magic UNO_QUERY is an element of a dummy enum, that allows to have a 2nd constructor which takes an interface reference as an argument) performs a queryInterface on r for the interface (here XInputStream and XOutputStream), the results are stored within the references.