Class/Object

net.liftweb.http

RequestVar

Related Docs: object RequestVar | package http

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abstract class RequestVar[T] extends AnyVar[T, RequestVar[T]] with HasLogUnreadVal

A typesafe container for data with a lifetime nominally equivalent to the lifetime of a page rendered by an HTTP request. RequestVars maintain their value throughout the duration of the current HTTP request and any callbacks for servicing AJAX calls associated with the rendered page. RequestVar instances have no value at the beginning of request servicing (excluding AJAX callbacks) and their value is discarded at the end of request processing. They are commonly used to share values across many snippets. Basic usage:

object MySnippetCompanion { object myRequestVar extends RequestVar[String]("hello") }

The standard pattern is to create a singleton object extending RequestVar instead of creating an instance variable of a concrete RequestVar subclass. This is preferred because RequestVar will use the name of its instantiating class for part of its state maintenance mechanism.

If you find it necessary to create a RequestVar subclass of which there may be more than one instance, it is necessary to override the nameSalt() method to return a unique salt value for each instance to prevent name collisions.

Linear Supertypes
HasLogUnreadVal, AnyVar[T, RequestVar[T]], AnyVarTrait[T, RequestVar[T]], HasCalcDefaultValue[T], PSettableValueHolder[T], SettableValueHolder, Settable, PValueHolder[T], ValueHolder, AnyRef, Any
Known Subclasses
Ordering
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Inherited
  1. RequestVar
  2. HasLogUnreadVal
  3. AnyVar
  4. AnyVarTrait
  5. HasCalcDefaultValue
  6. PSettableValueHolder
  7. SettableValueHolder
  8. Settable
  9. PValueHolder
  10. ValueHolder
  11. AnyRef
  12. Any
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Visibility
  1. Public
  2. All

Instance Constructors

  1. new RequestVar(dflt: ⇒ T)

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    dflt

    - the default value to be returned if none was set prior to requesting a value to be returned from the container

Type Members

  1. type CleanUpParam = Box[LiftSession]

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    Definition Classes
    RequestVar → AnyVarTrait
  2. type FuncType = (Box[T], Boolean) ⇒ Unit

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    Definition Classes
    AnyVarTrait
  3. type ValueType = T

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    Definition Classes
    PValueHolder → ValueHolder

Value Members

  1. final def !=(arg0: Any): Boolean

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

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

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    Definition Classes
    AnyRef → Any
  4. def __nameSalt: String

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    Attributes
    protected
    Definition Classes
    AnyVarTrait
  5. def apply(what: T): T

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    Definition Classes
    AnyVarTrait
  6. final def asInstanceOf[T0]: T0

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    Definition Classes
    Any
  7. def atomicUpdate(f: (ValueType) ⇒ ValueType): ValueType

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    Definition Classes
    Settable
  8. def calcDefaultValue: T

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    Attributes
    protected
    Definition Classes
    AnyVar → AnyVarTrait → HasCalcDefaultValue
  9. def clearFunc(name: String): Unit

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait
  10. def clone(): AnyRef

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    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  11. def doSync[F](f: ⇒ F): F

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    Different Vars require different mechanisms for synchronization.

    Different Vars require different mechanisms for synchronization. This method implements the Var specific synchronization mechanism

    Definition Classes
    RequestVar → AnyVarTrait
  12. def doWith[F](newVal: T)(f: ⇒ F): F

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    Definition Classes
    AnyVarTrait
  13. final def eq(arg0: AnyRef): Boolean

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

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    Definition Classes
    AnyRef → Any
  15. def finalize(): Unit

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    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  16. def findFunc(name: String): Box[T]

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait
  17. final def generateSnapshotRestorer[T](): (() ⇒ T) ⇒ T

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    Generate a function that will take a snapshot of the current RequestVars such that they can be restored

  18. def get: T

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    Definition Classes
    AnyVarTrait → ValueHolder
  19. final def getClass(): Class[_]

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    Definition Classes
    AnyRef → Any
  20. def hashCode(): Int

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    Definition Classes
    AnyRef → Any
  21. def is: T

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    Definition Classes
    AnyVarTrait
  22. final def isInstanceOf[T0]: Boolean

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    Definition Classes
    Any
  23. def logUnreadVal: Boolean

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    This defines whether or not Lift will log when a RequestVar is set but then not read within the same request cycle.

    This defines whether or not Lift will log when a RequestVar is set but then not read within the same request cycle. Change this to false to turn off logging. Logging can also be turned off globally via LiftRules.logUnreadRequestVars.

    Definition Classes
    RequestVar → HasLogUnreadVal
    See also

    LiftRules#logUnreadRequestVars

  24. lazy val name: String

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    Attributes
    protected
    Definition Classes
    AnyVarTrait
  25. final def ne(arg0: AnyRef): Boolean

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    Definition Classes
    AnyRef
  26. final def notify(): Unit

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    Definition Classes
    AnyRef
  27. final def notifyAll(): Unit

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    Definition Classes
    AnyRef
  28. def onChange(f: FuncType): Unit

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    Definition Classes
    AnyVarTrait
  29. def onShutdown(session: CleanUpParam): Unit

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    Attributes
    protected
    Definition Classes
    AnyVarTrait
  30. def performAtomicOperation[T](f: ⇒ T): T

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    Definition Classes
    Settable
  31. def registerCleanupFunc(in: (Box[LiftSession]) ⇒ Unit): Unit

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait
  32. final def registerGlobalCleanupFunc(in: (CleanUpParam) ⇒ Unit): Unit

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    Attributes
    protected
    Definition Classes
    AnyVarTrait
  33. def remove(): Unit

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    Definition Classes
    AnyVarTrait
  34. def set(what: T): T

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    Definition Classes
    AnyVarTrait → Settable
  35. def setFunc(name: String, value: T): Unit

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait
  36. def setIfUnset(value: ⇒ T): T

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    Definition Classes
    AnyVarTrait
  37. def set_?: Boolean

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    Definition Classes
    AnyVarTrait
  38. def settingDefault_?: Boolean

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    Attributes
    protected
    Definition Classes
    AnyVarTrait
  39. def snapshot(): () ⇒ Unit

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    Return a function that, when applied, will set the value of the RequestVar to its current value

  40. def snapshotGroup: Box[RequestVarSnapshotGroup]

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    Is this RequestVar a member of a snapshot group? If so, specify the group here

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

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    Definition Classes
    AnyRef
  42. def testWasSet(name: String, bn: String): Boolean

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait
  43. def toString(): String

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    Definition Classes
    AnyVarTrait → AnyRef → Any
  44. def update(f: (T) ⇒ T): T

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    Definition Classes
    AnyVarTrait
  45. final def wait(): Unit

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

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

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    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  48. def wasInitialized(name: String, bn: String): Boolean

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    Attributes
    protected
    Definition Classes
    RequestVar → AnyVarTrait

Inherited from HasLogUnreadVal

Inherited from AnyVar[T, RequestVar[T]]

Inherited from AnyVarTrait[T, RequestVar[T]]

Inherited from HasCalcDefaultValue[T]

Inherited from PSettableValueHolder[T]

Inherited from SettableValueHolder

Inherited from Settable

Inherited from PValueHolder[T]

Inherited from ValueHolder

Inherited from AnyRef

Inherited from Any

Ungrouped