Temporary files for application deployment
By aseembajaj on Jul 24, 2009
After a user issues a deployment command, the application is whisked away by the deployment sub-system across the cluster to the appropriate managed server for deployment. We have often been asked questions about the fate of application file beyond this point and most of these questions are the in context of security manager configuration. Here is a brief overview of temporary files that are used during deployment of applications.
After handling the staging, the deployment sub-system hands over the file to containers for deployment. The containers assume the file to be available on the same machine and deal with it accordingly.
Archived applications are exploded in a sever-specific temporary directory and only the temporary location is looked at by the class loader. Exploded application directories are not copied to temporary directory. So the class loader for such an application directly looks up the original location. If such an exploded application has some archived modules (say web module), then they are exploded in a temporary directory as described earlier.
Jar files need not be exploded and are directly used by the class loader. But, for Windows, they are copied to a temporary directory and the class loader looks up the jar from the temporary location. This special treatment is done for usability as it lets users overwrite jar files.