ApplicationLifecycle

Application lifecycle register.

This is used to hook into Play lifecycle events, specifically, when Play is stopped. The reason Play only provides lifecycle callbacks for stopping is that constructors are considered the application start callback. This has several advantages:

- It simplifies implementation, if you want to start something, just do it in the constructor. - It simplifies state, there's no transitional state where an object has been created but not started yet. Hence, as long as you have a reference to something, it's safe to use it. - It solves startup dependencies in a type safe manner - the order that components must be started is enforced by the order that they must be instantiated due to the component graph.

Stop hooks are executed when the application is shutdown, in reverse from when they were registered. Due to this reverse ordering, a component can know that it is safe to use the components it depends on as long as it hasn't received a shutdown event.

To use this, declare a dependency on ApplicationLifecycle, and then register the stop hook when the component is started. For example:

import play.api.inject.ApplicationLifecycle
import javax.inject.Inject

class SomeDatabase @Inject() (applicationLifecycle: ApplicationLifecycle) {

  private val connectionPool = new SomeConnectionPool()
  applicationLifecycle.addStopHook { () =>
    connectionPool.shutdown()
  }

  ...
}

Source: ApplicationLifecycle.scala

Linear Supertypes

AnyRef, Any

Known Subclasses

DefaultApplicationLifecycle

Abstract Value Members

abstract def addStopHook(hook: () ⇒ Future[Unit]): Unit

Add a stop hook to be called when the application stops.
Add a stop hook to be called when the application stops.
The stop hook should redeem the returned future when it is finished shutting down. It is acceptable to stop immediately and return a successful future.

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def addStopHook(hook: Callable[Promise[Void]]): Unit

Add a stop hook to be called when the application stops.
Add a stop hook to be called when the application stops.
The stop hook should redeem the returned future when it is finished shutting down. It is acceptable to stop immediately and return a successful future.
final def asInstanceOf[T0]: T0

Definition Classes
Any
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )

Related Doc: package inject

trait ApplicationLifecycle extends AnyRef

Abstract Value Members

abstract def addStopHook(hook: () ⇒ Future[Unit]): Unit

Concrete Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

def addStopHook(hook: Callable[Promise[Void]]): Unit

final def asInstanceOf[T0]: T0

def clone(): AnyRef

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

Inherited from AnyRef

Inherited from Any

Ungrouped