The JarFileContainer are supposed to only be used by daemon class so the real implementation
are in project Daemon. However, the AppJar is also transfered by ApplicationMaster which has
a JarFileContainer. To avoid the serialization of JarFileContainer implementation in
application layer, we use JarFileContainerWrapper to wrap the real object.
The JarFileContainer are supposed to only be used by daemon class so the real implementation are in project Daemon. However, the AppJar is also transfered by ApplicationMaster which has a JarFileContainer. To avoid the serialization of JarFileContainer implementation in application layer, we use JarFileContainerWrapper to wrap the real object.