| VOCL was introduced to integrate the OCL into the UML for visual aspects. A semiformal foundation of VOCL was defined with the MOF approach that was already used for UML by the OMG. For this reason VOCL extends the UML meta model and the complete definition of UML and VOCL is integrated in just one composed meta model. OCL constraints describe the conditions that have to hold for instances of the meta model. |
There are four parts of the meta model of VOCL. The first part in figure 1.1 includes the structure of constraints with their context, conditions and navigation expressions, which consist of paths. |
