# Freeze

## Overview

### module Freeze

Freeze provides automatic persistence for Ice servants.

## Interface Index

BackgroundSaveEvictor
  A background-save evictor is an evictor that saves updates asynchronously in a background thread.
Connection
  A connection to a database (database environment with Berkeley DB).
Evictor
  An automatic Ice object persistence manager, based on the evictor pattern.
EvictorIterator
  An iterator for the objects managed by the evictor.
ServantInitializer
  A servant initializer provides the application with an opportunity to perform custom servant initialization.
Transaction
  A transaction.
TransactionalEvictor
  A transactional evictor is an evictor that performs every single read-write operation within its own transaction.

## Exception Index

DatabaseException
  A Freeze database exception.
DeadlockException
  A Freeze database deadlock exception.
EvictorDeactivatedException
  This exception is raised if the evictor has been deactivated.
IndexNotFoundException
  Exception raised when Freeze fails to locate an index
InvalidPositionException
  This Freeze Iterator is not on a valid position, for example this position has been erased.
NoSuchElementException
  This exception is raised if there are no further elements in the iteration.
NotFoundException
  A Freeze database exception, indicating that a database record could not be found.
TransactionAlreadyInProgressException
  An attempt was made to start a transaction while a previous transaction has not yet been committed or rolled back.

## Structure Index

CatalogData
  The catalog keeps information about Freeze Maps and Freeze evictors in a Berkeley Db environment.
ObjectRecord
  The evictor uses a number of maps with ::Ice::Identity keys and ObjectRecord values as its persistent storage.
Statistics
  The evictor maintains statistics about each object.

## Sequence Index

Key
  A database key, represented as a sequence of bytes.
Value
  A database value, represented as a sequence of bytes.

## Sequences

sequence<byte> Key

  A database key, represented as a sequence of bytes.

sequence<byte> Value

  A database value, represented as a sequence of bytes.