opjlarchive and opjlrestore - logical archive and restore a quiescent OPJ store

SYNOPSIS

    opjlarchive -config config-pathname [ other-opj-options ] -file archive-pathname
    opjlrestore -config config-pathname [ other-opj-options ] -file archive-pathname

DESCRIPTION

The logical archive facility provides a way to produce a logical archive of a persistent store into a file. An archive file can then be restored into a fresh OPJ store to create a store that is semantically equivalent to the original. This is how to migrate data from one version of OPJ to another.

Unlike the physical persistent store, the archive uses a portable file format that is not dependant on any particular PJama version or machine architecture. Archive/restore can be used to migrate data between different versions of PJama, different store architectures, and different machine architectures. The archive data format does not yet support persistent threads, so only quiescent stores can be safely archived.

An archive contains all of the persistent roots, all of the transient marks on persistent classes, all of the registered runtime listeners, and any reachable classes and data. The "identity" of each object is carefully recorded so that the result of a restore from an archive is indistinguishable from the original. For example, the identity hash code of a restored object is the same as for the original object.

    opjlarchive -config config-pathname [ other-opj-options ] -file archive-pathname

produces a logical archive of the entire store into a file of the given name. You should run this command using the same version of OPJ that created the store that you are archiving.

    opjlrestore -config config-pathname [ other-opj-options ] -file archive-pathname

Restores a persistent store from a logical archive. The set of persistent roots, listeners, transient marks from the archive, and all persistent data are restored in a fresh computation (VM activation). Resume listeners of restored objects and classes are invoked to indicate that the store is continuing from a previous checkpoint. Finally, the restored computation is stabilized, leaving a new stable store with the restored data.

N.B.The restore operation expects to create a new persistent store. If, instead, the persistent store identified by the configuration file already exists, the effect of the restore is undefined.