org.wandora.modules

Interface Module

All Known Subinterfaces:

ActionExceptionHandler, CacheService, DatabaseInterface, ModifyableUserStore, ModulesWebApp, ReplacementsModule, ServletModule, TemplateContextProvider, TopicMapManager, UserAuthenticator, UserStore

All Known Implementing Classes:

AbstractAction, AbstractControlledContext, AbstractModule, AbstractTemplate, AbstractTopicWebApp, AbstractWebApp, Axis2Service, BasicUserAuthenticator, BrowserPluginService, BundleContext, CachedAction, ChainedAction, ChangeUserAction, ChangeUserRolesAction, DatabaseUserStore, DBTesterModule, DefaultReplacementsModule, DiskCacheModule, EmailModule, FileUserStore, FNGAPIAction, FNGAPIExceptionHandler, FNGAPIWebApp, FrequencyRestrictedContext, GenericContext, GenericDatabaseInterface, GenericTemplateAction, GetUserAuthenticator, GetUserLogAction, GraphMLWebApp, IIIFWebApp, ImageResizeAction, JettyModule, JTMWebApp, LoggingModule, ModuleBundle, ModuleGroup, ModulesServlet._ServletModule, ModulesWandoraWebAppHandler._ServletModule, NetAuthenticatorModule, NewAPIKeyAction, PasswordResendAction, RDFWebApp, RecaptchaAction, RedirectAction, RequestForwarder, RoleRestrictedContext, SameAsService, ScopedModuleManager, ScreenCastWebApp, ScriptModule, SendEmailAction, SimpleTopicMapManager, SourceRestrictedContext, StaticContentAction, StaticTemplateContextProvider, StaticUserStore, TemplateActionExceptionHandler, TemplateManager, UserLoggerAction, UserManagerAction, UserStoreCopyTool, VelocityEngineModule, VelocityTemplate, ViewTopicAction, ViewTopicWebApp, WaianaService, WandoraModuleManager, WandoraServletModule, WandoraTopicMapManager, XTMWebApp

public interface Module

The interface all modules must implement. Typically you will want to extend AbstractModule instead of implementing this directly. It'll contain basic implementation for all methods and perform some commonly needed functions.

Author:

olli

Method Summary

Modifier and Type	Method and Description
java.util.Collection<Module>	getDependencies(ModuleManager manager) Returns all the modules this module depends on.
void	init(ModuleManager manager, java.util.HashMap<java.lang.String,java.lang.Object> parameters) Initialises the module.
boolean	isInitialized() Checks if the module is initialised.
boolean	isRunning() Checks if the module is running.
void	start(ModuleManager manager) Starts the module.
void	stop(ModuleManager manager) Stops the module.

Method Detail

init

void init(ModuleManager manager,
          java.util.HashMap<java.lang.String,java.lang.Object> parameters)
   throws ModuleException

Initialises the module. After constructor, this is the first method called in the life cycle of a module. It should not perform anything time consuming or anything with notable outside side effects. It should only read the parameters and initialise the module so that it can later be started. Note that a module being initialised doesn't mean that it necessarily will ever be started.

A ModuleException may be thrown if something vital is missing from the parameters or they are not sensible. In some cases you may not want to throw an exception even if vital initialisation information is missing. If, for example, it is possible that the module is initialised in some other way between the init and the start method calls. A ModuleException may also be thrown at the start method if the module is still not initialised.

Parameters:

manager - The module manager handling this module. You may keep a reference to it if needed.

parametersThe - module parameters parsed from the configuration file.

Throws:

ModuleException

getDependencies

java.util.Collection<Module> getDependencies(ModuleManager manager)
                                      throws ModuleException

Returns all the modules this module depends on. This method will be called after init and the dependencies are allowed to depend on the parameters passed to init. The modules that this module depends on must be returned as a collection. In addition, if any required module is not present, a MissingDependencyException should be thrown. Typically you will use the requireModule and optionalModule methods of the manager to make sure that the modules exist and add them to the collection. requireModule will automatically throw the exception too if the module is not found whereas optionalModule does not.

Parameters:

manager - The module manager handling this module.

Returns:

A collection of modules this module depends on.

Throws:

ModuleException

start

void start(ModuleManager manager)
    throws ModuleException

Starts the module. This will be called after init and getDependencies and signals that the module should now begin to perform whatever it was designed to do. This method call however should not block for long, so any time consuming tasks should be started in their own threads. You will typically get references to the required modules again in start using the findModule method of the manager and then store those references to instance variables for later use. You may throw a ModuleException if the module is not in a state where it can be started or it immediately becomes obvious that it cannot be started with the provided settings.

Parameters:

manager - The module manager handling this module.

Throws:

ModuleException

stop

void stop(ModuleManager manager)

Stops the module. Should stop all threads used by the module, free any large data structures and perform other cleanup. It is possible that the module will be started again later with a start method call (and foregoing init and getDependencies calls). The module should be left in a state where this is possible.

Parameters:

manager - The module manager handling this module.

isInitialized

boolean isInitialized()

Checks if the module is initialised. Should return true if init has been called and it did not throw an exception.

Returns:

isRunning

boolean isRunning()

Checks if the module is running. Should return true if start has been called and it did not throw an exception and stop has not been called yet.

Returns: