Component-based software engineering (CBSE) begins to reach a certain level of maturity. Indeed, for the development of complex applications the use of component paradigm has become common. Therefore, the evaluation of the quality of these applications becomes necessary. In this context, the use of metrics is considered very important. Several metrics specific to component-based applications have been proposed. However, any of these metrics gained the consensus of the CBSE community and mainly there is no proposed tool to support them. As a large part of frameworks for component-based application development is based on object-oriented technology, we propose to use some object-oriented (OO) metrics to evaluate component-based applications produced with this kind of framework. Indeed, these metrics became a standard in OO community. So, they are well-defined, well-known and empirically validated. To identify which object-oriented metrics are useful for the evaluation of component-based applications, we have conducted an experimental study on 10 OSGi applications. This study also gives us the opportunity to discuss on the respect by OSGi developers of some properties pointed out by the literature