With the development of the business process the new concept ”°process fragment”± becomes more important. The process will be executed step by step with the selection, composition and migration. The selection means that the next matched fragment will be selected from the repository, and then the newly selected fragment will be composed with the current fragment. That is to say, there is a new fragment definition. So the fragment instance will be migrated from the old definition to the new definition.

During the execution of the process fragment the exception will happen. In order to handle the exception, there are two strategies used. One of them is the forward recovery strategy, which is also called as the repair strategy; one of them is backward recovery strategy, which is also called compensate strategy.

The repair strategy can repair the exception in the execution of the process fragment. After the exception has been repaired, the execution of the process fragment can run as usual.

The compensate strategy will compensate the faulted affect fragment. That is to say, if the exception cannot be repaired, another way must be chosen to achieve the goal of the process.

Therefore the important questions are how the exception can be thrown and caught during the exception of the process fragment? How can be the exception classified? That is to say, how will be the matched strategy chosen? These questions will be answered in this thesis.