com.atlassian.jira.component.pico

Class ComponentManager

java.lang.Object

com.atlassian.jira.component.pico.ComponentManager

All Implemented Interfaces:

Shutdown

@Internal
 @ParametersAreNonnullByDefault
public class ComponentManager
extends Object
implements Shutdown

Manages Jira's ComponentContainer, which includes:

• Creating it
• Disposing of it
• Re-creating it
• Changing its ComponentContainer.ContainerLevel

It also provides lookup methods for obtaining components, such as getComponent(Class). Plugins developers should use ComponentAccessor for this, instead. This class is a stateful singleton that lasts for the entire uptime of Jira, but the container it manages will come and go as Jira goes through different stages of its lifecycle.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ComponentManager.PluginSystemState
static interface	ComponentManager.State The state of the ComponentManager.

Method Summary

Modifier and Type	Method and Description
boolean	componentsAvailable() Determines whether components have already been instantiated regardless of which container is in use.
void	createBootstrapContainer() Creates the ComponentContainer that contains the minimal components required to bootstrap Jira.
void	createFullContainer() Creates the ComponentContainer that contains the full set of Jira components.
<T> T	createRequestScopedComponent(Class<T> componentClass) Creates a request-scoped component of the given class.
void	discardContainer() Gets rid of the ComponentContainer and resets the state to ComponentManagerStateImpl.NOT_STARTED.
void	earlyStartPluginSystem() Early-starts the plugin system (including Plugins 1 components) and instantiates the components in the container.
void	extendBootstrapContainerForDisplayingErrors() Extends the bootstrap container by adding the extra components needed for displaying startup errors (or warnings) on the Johnson page.
void	extendBootstrapContainerForSetup() Extends the bootstrap container by adding the extra components needed for the admin to set up Jira.
<T> T	getComponent(Class<T> componentClass) Retrieves and returns a component which is an instance of given class.
<T> T	getComponentInstanceOfType(Class<T> type) Retrieves and returns a component which is an instance of given class.
<T> List<T>	getComponents(Class<T> type) Returns the components of the given type.
<T> List<T>	getComponentsOfType(Class<T> type) Returns all the components inside Pico that are instances of the given class.
<T> Map<String,T>	getComponentsOfTypeMap(Class<T> type) Returns all the components currently inside Pico which are instances of the given class, mapping them to their component key.
static ComponentManager	getInstance() Retuns a singleton instance of this class.
<T> T	getOSGiComponentInstanceOfType(Class<T> clazz) Deprecated. since 6.0 - please use the jira-api ComponentAccessor.getOSGiComponentInstanceOfType(Class) instead
ComponentManager.PluginSystemState	getPluginSystemState() Returns the state of the plugin system.
ComponentManager.State	getState() Returns the ComponentManager.State of this instance.
void	lateStartPluginSystem() Start delayed plugins (if any).
<T> T	loadComponent(Class<T> componentClass, Collection<Object> dependencies) Instantiates a component from its class and dependent classes/instances.
void	registerComponent(Class<?> interfaceClass, Class<?> componentClass) Registers a component of the given class, optionally using the given interface as the key.
void	restart() Stops the plugin system, replaces any container with a new full container, and restarts the plugin system (early and late).
void	shutdown() Stops the plugin system and discards the ComponentContainer.
void	stopPluginSystem() Publishes a ComponentManagerShutdownEvent and shuts down the plugin system.
void	unregisterComponent(Class<?> interfaceClass, Class<?> componentClass) Unregisters a component of the given class, optionally using the given interface as the key.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getInstance

@Nonnull
public static ComponentManager getInstance()

Retuns a singleton instance of this class.

Returns:

a singleton instance of this class

createBootstrapContainer

public void createBootstrapContainer()

Creates the ComponentContainer that contains the minimal components required to bootstrap Jira. This is done before we know whether Jira has been set up or will otherwise start up properly.

Throws:

IllegalStateException - if a container already exists

extendBootstrapContainerForSetup

public void extendBootstrapContainerForSetup()

Extends the bootstrap container by adding the extra components needed for the admin to set up Jira.

Throws:

IllegalStateException - if there's no container, it's not initialised, or it's not in bootstrap mode

See Also:

createBootstrapContainer()

extendBootstrapContainerForDisplayingErrors

public void extendBootstrapContainerForDisplayingErrors()

Extends the bootstrap container by adding the extra components needed for displaying startup errors (or warnings) on the Johnson page. Does nothing if there's no container or it's already been extended.

Throws:

IllegalStateException - if there's an unextended container but it's either uninitialised or not in bootstrap mode

See Also:

createBootstrapContainer()

createFullContainer

public void createFullContainer()

Creates the ComponentContainer that contains the full set of Jira components.

Throws:

IllegalStateException - if a container already exists

earlyStartPluginSystem

public void earlyStartPluginSystem()

Early-starts the plugin system (including Plugins 1 components) and instantiates the components in the container. Lastly, transitions this manager to the ComponentManagerStateImpl.STARTED state and publishes a ComponentManagerStartedEvent.

lateStartPluginSystem

public void lateStartPluginSystem()

Start delayed plugins (if any).

See Also:

SplitStartupPluginSystemLifecycle.lateStartup()

componentsAvailable

public boolean componentsAvailable()

Determines whether components have already been instantiated regardless of which container is in use.

Returns:

true iff components have already been instantiated by the container in play

stopPluginSystem

public void stopPluginSystem()

Publishes a ComponentManagerShutdownEvent and shuts down the plugin system.

discardContainer

public void discardContainer()

Gets rid of the ComponentContainer and resets the state to ComponentManagerStateImpl.NOT_STARTED.

shutdown

public void shutdown()

Stops the plugin system and discards the ComponentContainer.

Specified by:

shutdown in interface Shutdown

See Also:

stopPluginSystem(), discardContainer()

getState

@Nonnull
public ComponentManager.State getState()

Returns the ComponentManager.State of this instance.

Returns:

the current state.

getPluginSystemState

public ComponentManager.PluginSystemState getPluginSystemState()

Returns the state of the plugin system. This can be used to discover whether delayed plugins were started.

Returns:

the current state of the plugin system

getComponentInstanceOfType

@Nullable
public <T> T getComponentInstanceOfType(Class<T> type)

Retrieves and returns a component which is an instance of given class.

In practise, this is the same as getComponent(Class) except it will try to find a unique component that implements/extends the given Class even if the Class is not an actual component key.

Please note that this method only gets components from JIRA's core Pico Containter. That is, it retrieves core components and components declared in Plugins1 plugins, but not components declared in Plugins2 plugins. Plugins2 components can be retrieved via the getOSGiComponentInstanceOfType(Class) method, but only if they are public. NOTE to Jira devs: don't use this method for general purpose component retrieval. Use ComponentAccessor instead.

Parameters:

type - the class by which to find the component

Returns:

found component

See Also:

getOSGiComponentInstanceOfType(Class), ComponentContainer#getComponent(Class))

getComponent

@Nullable
public <T> T getComponent(Class<T> componentClass)

Retrieves and returns a component which is an instance of given class.

In practise, this is the same as getComponentInstanceOfType(Class) except it will fail faster if the given Class is not a known component key (it also has a shorter and more meaningful name).

Please note that this method only gets components from JIRA's core Pico Container. That is, it retrieves core components and components declared in Plugins1 plugins, but not components declared in Plugins2 plugins. Plugins2 components can be retrieved via the getOSGiComponentInstanceOfType(Class) method, but only if they are public. NOTE to Jira DEVS: Stop using this method for general purpose component retrieval; use ComponentAccessor please.

Parameters:

componentClass - class to find a component instance by

Returns:

found component, or null if not found

See Also:

getOSGiComponentInstanceOfType(Class), ComponentContainer.getComponent(Class)

getOSGiComponentInstanceOfType

@Nullable
public <T> T getOSGiComponentInstanceOfType(Class<T> clazz)

Deprecated. since 6.0 - please use the jira-api ComponentAccessor.getOSGiComponentInstanceOfType(Class) instead

Retrieves and returns a public component from OSGi land via its class name. This method can be used to retrieve a component provided via a plugins2 OSGi bundle. Please note that components returned via this method should *NEVER* be cached (e.g. in a static field) as they may be refreshed at any time as a plugin is enabled/disabled or the componentManager is reinitialised (after an XML import).

Plugin developers should prefer the API method ComponentAccessor.getOSGiComponentInstanceOfType(Class).

It is important to note that this only works for public components. That is components with public="true" declared in their XML configuration. This means that they are available for other plugins to import.

A use case for this is when for example for the dashboards plugin. In several areas in JIRA we may want to render gadgets via the GadgetViewFactory. Whilst the interface for this component is available in JIRA core, the implementation is provided by the dashboards OSGi bundle. This method will allow us to access it. NOTE to JIRA DEVS : Stop using this method for general purpose component retrieval. Use ComponentAccessor please.

Parameters:

clazz - class to find an OSGi component instance for

Returns:

found component

See Also:

getComponentInstanceOfType(Class)

getComponents

public <T> List<T> getComponents(Class<T> type)

Returns the components of the given type.

Type Parameters:

T - the component type

Parameters:

type - the component type

Returns:

see above

Throws:

IllegalStateException - if the container does not exist

Since:

7.7

getComponentsOfType

public <T> List<T> getComponentsOfType(Class<T> type)

Returns all the components inside Pico that are instances of the given class.

Parameters:

type - the class for which to search

Returns:

see above

getComponentsOfTypeMap

public <T> Map<String,T> getComponentsOfTypeMap(Class<T> type)

Returns all the components currently inside Pico which are instances of the given class, mapping them to their component key.

Parameters:

type - the type for which to search

Returns:

a map, mapping the component key, to the instances of the class registered in JIRA's pico container.

registerComponent

public void registerComponent(@Nullable
                              Class<?> interfaceClass,
                              Class<?> componentClass)

Registers a component of the given class, optionally using the given interface as the key. Does nothing if there is no container in play.

Parameters:

interfaceClass - the interface to use as the key

componentClass - the component class

Since:

7.7

unregisterComponent

public void unregisterComponent(@Nullable
                                Class<?> interfaceClass,
                                Class<?> componentClass)

Unregisters a component of the given class, optionally using the given interface as the key.

Parameters:

interfaceClass - the interface to use as the key

componentClass - the component class

Since:

7.7

createRequestScopedComponent

public <T> T createRequestScopedComponent(Class<T> componentClass)

Creates a request-scoped component of the given class.

Type Parameters:

T - the type of the component

Parameters:

componentClass - the class of component to instantiate

Returns:

the component

Since:

7.7 moved from PicoWebworkObjectCreator

loadComponent

@Nullable
public <T> T loadComponent(Class<T> componentClass,
                                     Collection<Object> dependencies)

Instantiates a component from its class and dependent classes/instances.

Type Parameters:

T - the type of component

Parameters:

componentClass - the class of component to instantiate

dependencies - the component's dependencies (classes and/or instances)

Returns:

the component, or null if the component class is the Void class

Since:

7.7 moved from JiraUtils

restart

public void restart()

Stops the plugin system, replaces any container with a new full container, and restarts the plugin system (early and late). This should only be done:

• if you are importing,
• if you are setting up Jira, or
• during tests

Since:

7.7 was called globalRefresh() in now-deleted ManagerFactory class