Class Overview
This class extends ThreadLocal to provide inheritance of values
from parent thread to child thread: when a child thread is created, the
child receives initial values for all inheritable thread-local variables
for which the parent has values. Normally the child's values will be
identical to the parent's; however, the child's value can be made an
arbitrary function of the parent's by overriding the childValue
method in this class.
Inheritable thread-local variables are used in preference to
ordinary thread-local variables when the per-thread-attribute being
maintained in the variable (e.g., User ID, Transaction ID) must be
automatically transmitted to any child threads that are created.
Summary
Protected Methods |
T
|
childValue(T parentValue)
Computes the child's initial value for this inheritable thread-local
variable as a function of the parent's value at the time the child
thread is created.
|
[Expand]
Inherited Methods |
From class
java.lang.ThreadLocal
T
|
get()
Returns the value in the current thread's copy of this
thread-local variable.
|
T
|
initialValue()
Returns the current thread's "initial value" for this
thread-local variable.
|
void
|
remove()
Removes the current thread's value for this thread-local
variable.
|
void
|
set(T value)
Sets the current thread's copy of this thread-local variable
to the specified value.
|
|
From class
java.lang.Object
Object
|
clone()
Creates and returns a copy of this object.
|
boolean
|
equals(Object obj)
Indicates whether some other object is "equal to" this one.
|
void
|
finalize()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
|
final
Class<?>
|
getClass()
Returns the runtime class of this Object .
|
int
|
hashCode()
Returns a hash code value for the object.
|
final
void
|
notify()
Wakes up a single thread that is waiting on this object's
monitor.
|
final
void
|
notifyAll()
Wakes up all threads that are waiting on this object's monitor.
|
String
|
toString()
Returns a string representation of the object.
|
final
void
|
wait()
Causes the current thread to wait until another thread invokes the
notify() method or the
notifyAll() method for this object.
|
final
void
|
wait(long timeout, int nanos)
Causes the current thread to wait until another thread invokes the
notify() method or the
notifyAll() method for this object, or
some other thread interrupts the current thread, or a certain
amount of real time has elapsed.
|
final
void
|
wait(long timeout)
Causes the current thread to wait until either another thread invokes the
notify() method or the
notifyAll() method for this object, or a
specified amount of time has elapsed.
|
|
Public Constructors
public
InheritableThreadLocal
()
Protected Methods
protected
T
childValue
(T parentValue)
Computes the child's initial value for this inheritable thread-local
variable as a function of the parent's value at the time the child
thread is created. This method is called from within the parent
thread before the child is started.
This method merely returns its input argument, and should be overridden
if a different behavior is desired.
Parameters
parentValue
| the parent thread's value |
Returns
- the child thread's initial value