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ThreadLocal Class

Definition

This class provides thread-local variables.

[Android.Runtime.Register("java/lang/ThreadLocal", DoNotGenerateAcw=true)]
[Java.Interop.JavaTypeParameters(new System.String[] { "T" })]
public class ThreadLocal : Java.Lang.Object
[<Android.Runtime.Register("java/lang/ThreadLocal", DoNotGenerateAcw=true)>]
[<Java.Interop.JavaTypeParameters(new System.String[] { "T" })>]
type ThreadLocal = class
    inherit Object
Inheritance
ThreadLocal
Derived
Attributes

Remarks

This class provides thread-local variables. These variables differ from their normal counterparts in that each thread that accesses one (via its get or set method) has its own, independently initialized copy of the variable. ThreadLocal instances are typically private static fields in classes that wish to associate state with a thread (e.g., a user ID or Transaction ID).

For example, the class below generates unique identifiers local to each thread. A thread's id is assigned the first time it invokes ThreadId.get() and remains unchanged on subsequent calls.

import java.util.concurrent.atomic.AtomicInteger;

            public class ThreadId {
                // Atomic integer containing the next thread ID to be assigned
                private static final AtomicInteger nextId = new AtomicInteger(0);

                // Thread local variable containing each thread's ID
                private static final ThreadLocal&lt;Integer&gt; threadId =
                    new ThreadLocal&lt;Integer&gt;() {
                        &#64;Override protected Integer initialValue() {
                            return nextId.getAndIncrement();
                    }
                };

                // Returns the current thread's unique ID, assigning it if necessary
                public static int get() {
                    return threadId.get();
                }
            }

Each thread holds an implicit reference to its copy of a thread-local variable as long as the thread is alive and the ThreadLocal instance is accessible; after a thread goes away, all of its copies of thread-local instances are subject to garbage collection (unless other references to these copies exist).

Added in 1.2.

Java documentation for java.lang.ThreadLocal.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

ThreadLocal()

Creates a thread local variable.

ThreadLocal(IntPtr, JniHandleOwnership)

A constructor used when creating managed representations of JNI objects; called by the runtime.

Properties

Class

Returns the runtime class of this Object.

(Inherited from Object)
Handle

The handle to the underlying Android instance.

(Inherited from Object)
JniIdentityHashCode (Inherited from Object)
JniPeerMembers
PeerReference (Inherited from Object)
ThresholdClass

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

ThresholdType

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

Methods

Clone()

Creates and returns a copy of this object.

(Inherited from Object)
Dispose() (Inherited from Object)
Dispose(Boolean) (Inherited from Object)
Equals(Object)

Indicates whether some other object is "equal to" this one.

(Inherited from Object)
Get()

Returns the value in the current thread's copy of this thread-local variable.

GetHashCode()

Returns a hash code value for the object.

(Inherited from Object)
InitialValue()

Returns the current thread's "initial value" for this thread-local variable.

JavaFinalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

(Inherited from Object)
Notify()

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

(Inherited from Object)
NotifyAll()

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

(Inherited from Object)
Remove()

Removes the current thread's value for this thread-local variable.

Set(Object)

Sets the current thread's copy of this thread-local variable to the specified value.

SetHandle(IntPtr, JniHandleOwnership)

Sets the Handle property.

(Inherited from Object)
ToArray<T>() (Inherited from Object)
ToString()

Returns a string representation of the object.

(Inherited from Object)
UnregisterFromRuntime() (Inherited from Object)
Wait()

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>.

(Inherited from Object)
Wait(Int64, Int32)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)
Wait(Int64)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)
WithInitial(ISupplier)

Creates a thread local variable.

Explicit Interface Implementations

IJavaPeerable.Disposed() (Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced() (Inherited from Object)
IJavaPeerable.Finalized() (Inherited from Object)
IJavaPeerable.JniManagedPeerState (Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32) (Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates) (Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference) (Inherited from Object)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to