Provides a decorator container that is able to store records (of type {@link xxl.core.io.Block} ) which are of different size. The size of each record has to be below a maximum size which is again below the pageSize.

A RecordManager can be used on top of each container. Usually, it is used on top of a {@link xxl.core.collections.containers.io.BlockFileContainer} or a {@link xxl.core.collections.containers.io.MultiBlockContainer} .