net.liftweb.http

ContainerVar

class ContainerVar [T] extends AnyVar[T, ContainerVar[T]] with LazyLoggable

A typesafe container for data with a lifetime nominally equivalent to the lifetime of HttpSession attributes. This alternative to SessionVar keeps data in the container's session and must be serializable to support session migration. Use SessionVars unless you are using MigratoryLiftSessions.

<code> object MySnippetCompanion { object mySessionVar extends ContainerVar[String]("hello") } </code>

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

If you find it necessary to create a ContainerVar 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.

attributes: abstract
linear super types: LazyLoggable, AnyVar[T, ContainerVar[T]], AnyVarTrait[T, ContainerVar[T]], HasCalcDefaultValue[T], PSettableValueHolder[T], SettableValueHolder, Settable, PValueHolder[T], ValueHolder, AnyRef, Any
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  1. ContainerVar
  2. LazyLoggable
  3. AnyVar
  4. AnyVarTrait
  5. HasCalcDefaultValue
  6. PSettableValueHolder
  7. SettableValueHolder
  8. Settable
  9. PValueHolder
  10. ValueHolder
  11. AnyRef
  12. Any
Visibility
  1. Public
  2. All
Impl.
  1. Concrete
  2. Abstract

Instance constructors

  1. new ContainerVar (dflt: ⇒ T)(implicit containerSerializer: ContainerSerializer[T])

    dflt

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

    containerSerializer

    -- an implicit parameter that keeps us honest about only storing things that can be actually serialized. Lift provides a subset of these.

Type Members

  1. type CleanUpParam = LiftSession

    definition classes: ContainerVarAnyVarTrait
  2. type ValueType = T

    definition classes: PValueHolderValueHolder

Value Members

  1. def != (arg0: AnyRef) : Boolean

    attributes: final
    definition classes: AnyRef
  2. def != (arg0: Any) : Boolean

    o != arg0 is the same as !(o == (arg0)).

    o != arg0 is the same as !(o == (arg0)).

    arg0

    the object to compare against this object for dis-equality.

    returns

    false if the receiver object is equivalent to the argument; true otherwise.

    attributes: final
    definition classes: Any
  3. def ## () : Int

    attributes: final
    definition classes: AnyRef → Any
  4. def $asInstanceOf [T0] () : T0

    attributes: final
    definition classes: AnyRef
  5. def $isInstanceOf [T0] () : Boolean

    attributes: final
    definition classes: AnyRef
  6. def == (arg0: AnyRef) : Boolean

    o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).

    o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    attributes: final
    definition classes: AnyRef
  7. def == (arg0: Any) : Boolean

    o == arg0 is the same as o.equals(arg0).

    o == arg0 is the same as o.equals(arg0).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    attributes: final
    definition classes: Any
  8. def __nameSalt : String

    attributes: protected
    definition classes: AnyVarTrait
  9. def apply (what: T) : T

    Set the session variable

    Set the session variable

    what

    -- the value to set the session variable to

    definition classes: AnyVarTrait
  10. def asInstanceOf [T0] : T0

    This method is used to cast the receiver object to be of type T0.

    This method is used to cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expressionList(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested typed.

    returns

    the receiver object.

    attributes: final
    definition classes: Any
  11. def atomicUpdate (f: (ValueType) ⇒ ValueType) : ValueType

    Perform an atomic update of this Settable.

    Perform an atomic update of this Settable. The current value is passed to the function and the ValueHolder is set to the result of the function. This is enclosed in the performAtomicOperation method which will, by default, synchronize this instance

    definition classes: Settable
  12. def calcDefaultValue : T

    attributes: protected
    definition classes: AnyVarAnyVarTraitHasCalcDefaultValue
  13. def clearFunc (name: String) : Unit

    attributes: protected
    definition classes: ContainerVarAnyVarTrait
  14. def clone () : AnyRef

    This method creates and returns a copy of the receiver object.

    This method creates and returns a copy of the receiver object.

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object.

    attributes: protected
    definition classes: AnyRef
  15. def doSync [F] (f: ⇒ F) : F

    Different Vars require different mechanisms for synchronization.

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

    In the case of ContainerVar, we synchronize on the ContainerVar instance itself.

    definition classes: ContainerVarAnyVarTrait
  16. def doWith [F] (newVal: T)(f: ⇒ F) : F

    Change the value of the Var for the lifespan of the function

    Change the value of the Var for the lifespan of the function

    definition classes: AnyVarTrait
  17. def eq (arg0: AnyRef) : Boolean

    This method is used to test whether the argument (arg0) is a reference to the receiver object (this).

    This method is used to test whether the argument (arg0) is a reference to the receiver object (this).

    The eq method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on non-null instances of AnyRef: * It is reflexive: for any non-null instance x of type AnyRef, x.eq(x) returns true. * It is symmetric: for any non-null instances x and y of type AnyRef, x.eq(y) returns true if and only if y.eq(x) returns true. * It is transitive: for any non-null instances x, y, and z of type AnyRef if x.eq(y) returns true and y.eq(z) returns true, then x.eq(z) returns true.

    Additionally, the eq method has three other properties. * It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false. * For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false. * null.eq(null) returns true.

    When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).

    arg0

    the object to compare against this object for reference equality.

    returns

    true if the argument is a reference to the receiver object; false otherwise.

    attributes: final
    definition classes: AnyRef
  18. def equals (arg0: Any) : Boolean

    This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.

    This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.

    The default implementations of this method is an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation]: * It is reflexive: for any instance x of type Any, x.equals(x) should return true. * It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true. * It is transitive: for any instances x, y, and z of type AnyRef if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

    If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is often necessary to override hashCode to ensure that objects that are "equal" (o1.equals(o2) returns true) hash to the same scala.Int (o1.hashCode.equals(o2.hashCode)).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    definition classes: AnyRef → Any
  19. def finalize () : Unit

    This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.

    This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.

    The details of when and if the finalize method are invoked, as well as the interaction between finalizeand non-local returns and exceptions, are all platform dependent.

    attributes: protected
    definition classes: AnyRef
  20. def findFunc (name: String) : Box[T]

    attributes: protected
    definition classes: ContainerVarAnyVarTrait
  21. def get : T

    Shadow of the 'is' method

    Shadow of the 'is' method

    definition classes: AnyVarTraitValueHolder
  22. def getClass () : java.lang.Class[_]

    Returns a representation that corresponds to the dynamic class of the receiver object.

    Returns a representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

    a representation that corresponds to the dynamic class of the receiver object.

    attributes: final
    definition classes: AnyRef
  23. def hashCode () : Int

    Returns a hash code value for the object.

    Returns a hash code value for the object.

    The default hashing algorithm is platform dependent.

    Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

    returns

    the hash code value for the object.

    definition classes: AnyRef → Any
  24. def is : T

    The current value of the variable

    The current value of the variable

    definition classes: AnyVarTraitValueHolder
  25. def isInstanceOf [T0] : Boolean

    This method is used to test whether the dynamic type of the receiver object is T0.

    This method is used to test whether the dynamic type of the receiver object is T0.

    Note that the test result of the test is modulo Scala's erasure semantics. Therefore the expression1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested typed.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    attributes: final
    definition classes: Any
  26. lazy val logger : Logger

    attributes: protected
    definition classes: LazyLoggable
  27. lazy val name : String

    attributes: protected
    definition classes: AnyVarTrait
  28. def ne (arg0: AnyRef) : Boolean

    o.ne(arg0) is the same as !(o.eq(arg0)).

    o.ne(arg0) is the same as !(o.eq(arg0)).

    arg0

    the object to compare against this object for reference dis-equality.

    returns

    false if the argument is not a reference to the receiver object; true otherwise.

    attributes: final
    definition classes: AnyRef
  29. def notify () : Unit

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    attributes: final
    definition classes: AnyRef
  30. def notifyAll () : Unit

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    attributes: final
    definition classes: AnyRef
  31. def onShutdown (session: CleanUpParam) : Unit

    attributes: protected
    definition classes: AnyVarTrait
  32. def performAtomicOperation [T] (f: ⇒ T) : T

    Perform an atomic operation on the Settable.

    Perform an atomic operation on the Settable. By default synchronizes the instance, but it could use other mechanisms

    definition classes: Settable
  33. def registerCleanupFunc (in: (LiftSession) ⇒ Unit) : Unit

    attributes: protected
    definition classes: ContainerVarAnyVarTrait
  34. def registerGlobalCleanupFunc (in: (CleanUpParam) ⇒ Unit) : Unit

    attributes: protected final
    definition classes: AnyVarTrait
  35. def remove () : Unit

    definition classes: AnyVarTrait
  36. def set (what: T) : T

    Shadow of the apply method

    Shadow of the apply method

    definition classes: AnyVarTraitSettable
  37. def setFunc (name: String, value: T) : Unit

    attributes: protected
    definition classes: ContainerVarAnyVarTrait
  38. def setIsUnset (value: ⇒ T) : T

    Set the Var if it has not been calculated

    Set the Var if it has not been calculated

    definition classes: AnyVarTrait
  39. def set_? : Boolean

    Has this Var been set or accessed and had its default value calculated

    Has this Var been set or accessed and had its default value calculated

    definition classes: AnyVarTrait
  40. def settingDefault_? : Boolean

    attributes: protected
    definition classes: AnyVarTrait
  41. def showWarningWhenAccessedOutOfSessionScope_? : Boolean

  42. def synchronized [T0] (arg0: T0) : T0

    attributes: final
    definition classes: AnyRef
  43. def testWasSet (name: String) : Boolean

    A non-side-effecting test if the value was initialized

    A non-side-effecting test if the value was initialized

    attributes: protected
    definition classes: ContainerVarAnyVarTrait
  44. def toString () : String

    Returns a string representation of the object.

    Returns a string representation of the object.

    The default representation is platform dependent.

    returns

    a string representation of the object.

    definition classes: AnyVarTrait → AnyRef → Any
  45. def update (f: (T) ⇒ T) : T

    Applies the given function to the contents of this variable and sets the variable to the resulting value.

    Applies the given function to the contents of this variable and sets the variable to the resulting value.

    f

    -- the function to apply and set the result from.

    definition classes: AnyVarTrait
  46. def wait () : Unit

    attributes: final
    definition classes: AnyRef
  47. def wait (arg0: Long, arg1: Int) : Unit

    attributes: final
    definition classes: AnyRef
  48. def wait (arg0: Long) : Unit

    attributes: final
    definition classes: AnyRef
  49. def wasInitialized (name: String) : Boolean

    attributes: protected
    definition classes: ContainerVarAnyVarTrait

Inherited from LazyLoggable

Inherited from AnyVar[T, ContainerVar[T]]

Inherited from AnyVarTrait[T, ContainerVar[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