Interface PersistentService

All Known Implementing Classes:
StorageFactoryService
public interface PersistentService
A PersistentService modularises the access to persistent services, abstracting out details such as finding the list of services to be started at boot time, finding the service.properties file and creating and deleting the persistent storage for a service.

These modules must only be used by the monitor.

Possible examples of implementations are:

  • Store services in a directory in the file system.
  • Store services in a zip file
  • Service data is provided by a web server
  • Service data is stored on the class path.

This class also serves as the registry the defined name for all the implementations of PersistentService. These need to be kept track of as they can be used in JDBC URLS.

An implementation of PersistentService can implement ModuleSupportable but must not implement ModuleControl. This is because the monitor will not execute ModuleControl methods for a PersistentService.

  • Field Details

  • Method Details

    • getType

      String getType()
      Return the type of this service.

    • getBootTimeServices

      Enumeration getBootTimeServices()
      Return an Enumeration of service names descriptors (Strings) that should be be started at boot time by the monitor. The monitor will boot the service if getServiceProperties() returns a Properties object and the properties does not indicate the service should not be auto-booted.

      This method may return null if there are no services that need to be booted automatically at boot time.

      The service name returned by the Enumeration must be in its canonical form.

    • createDataWarningFile

      void createDataWarningFile(StorageFactory sf) throws StandardException
      Put a readme file in database directory which will caution users against touching any files in the directory. This file will be created at database creation time.
      Parameters:
      sf - StorageFactory will be used to create the file
      Throws:
      StandardException - File can't be created

    • getServiceProperties

      Properties getServiceProperties(String serviceName, Properties defaultProperties) throws StandardException
      For a service return its service properties, typically from the service.properties file.
      Returns:
      A Properties object or null if serviceName does not represent a valid service.
      Throws:
      StandardException - Service appears valid but the properties cannot be created.

    • saveServiceProperties

      void saveServiceProperties(String serviceName, StorageFactory storageFactory, Properties properties, boolean replace) throws StandardException
      Throws:
      StandardException - Properties cannot be saved.

    • saveServiceProperties

      void saveServiceProperties(String serviceName, Properties properties) throws StandardException
      Save to a backup file.
      Throws:
      StandardException - Properties cannot be saved.

    • createServiceRoot

      String createServiceRoot(String name, boolean deleteExisting) throws StandardException
      Returns the canonical name of the service.
      Throws:
      StandardException - Service root cannot be created.

    • removeServiceRoot

      boolean removeServiceRoot(String serviceName)
      Remove a service's root and its contents.

    • getCanonicalServiceName

      String getCanonicalServiceName(String name) throws StandardException
      Convert a service name into its canonical form. Returns null if the name cannot be converted into a canonical form.
      Throws:
      StandardException - if an error happens when converting the name (name probably invalid)

    • getUserServiceName

      String getUserServiceName(String serviceName)
      Return the user form of a service name. This name is only valid within this system. The separator character used must be '/'

    • isSameService

      boolean isSameService(String serviceName1, String serviceName2)

    • hasStorageFactory

      boolean hasStorageFactory()
      Returns:
      true if the PersistentService has a StorageFactory, false if not.

    • getStorageFactoryInstance

      StorageFactory getStorageFactoryInstance(boolean useHome, String databaseName, String tempDirName, String uniqueName) throws StandardException, IOException
      Get an initialized StorageFactoryInstance
      Parameters:
      useHome - If true and the database name is not absolute then the database directory will be relative to the home directory, if one is defined in the properties file.
      databaseName - The name of the database (directory). The name does not include the subSubProtocol. If null then the storage factory will only be used to deal with the directory containing the databases.
      tempDirName - The name of the temporary file directory set in properties. If null then a default directory should be used. Each database should get a separate temporary file directory within this one to avoid collisions.
      uniqueName - A unique name that can be used to create the temporary file directory for this database. If null then temporary files will not be created in this StorageFactory instance.
      Returns:
      An initialized StorageFactory.
      Throws:
      StandardException
      IOException