Monitor.Enter Méthode
Définition
Important
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Acquiert un verrou exclusif sur l'objet spécifié.
Surcharges
Enter(Object) |
Acquiert un verrou exclusif sur l'objet spécifié. |
Enter(Object, Boolean) |
Acquiert un verrou exclusif sur l'objet spécifié et définit de manière atomique une valeur qui indique si le verrou a été pris. |
Enter(Object)
Acquiert un verrou exclusif sur l'objet spécifié.
public:
static void Enter(System::Object ^ obj);
public static void Enter (object obj);
static member Enter : obj -> unit
Public Shared Sub Enter (obj As Object)
Paramètres
- obj
- Object
Objet sur lequel acquérir le verrou du moniteur.
Exceptions
Le paramètre obj
a la valeur null
.
Exemples
L'exemple suivant décrit comment utiliser la méthode Enter
.
#using <System.dll>
using namespace System;
using namespace System::Threading;
using namespace System::Collections::Generic;
using namespace System::Text;
generic <typename T> public ref class SafeQueue
{
private:
// A queue that is protected by Monitor.
Queue<T>^ m_inputQueue;
public:
SafeQueue()
{
m_inputQueue = gcnew Queue<T>();
};
// Lock the queue and add an element.
void Enqueue(T qValue)
{
// Request the lock, and block until it is obtained.
Monitor::Enter(m_inputQueue);
try
{
// When the lock is obtained, add an element.
m_inputQueue->Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
};
// Try to add an element to the queue: Add the element to the queue
// only if the lock is immediately available.
bool TryEnqueue(T qValue)
{
// Request the lock.
if (Monitor::TryEnter(m_inputQueue))
{
try
{
m_inputQueue->Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
return true;
}
else
{
return false;
}
};
// Try to add an element to the queue: Add the element to the queue
// only if the lock becomes available during the specified time
// interval.
bool TryEnqueue(T qValue, int waitTime)
{
// Request the lock.
if (Monitor::TryEnter(m_inputQueue, waitTime))
{
try
{
m_inputQueue->Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
return true;
}
else
{
return false;
}
};
// Lock the queue and dequeue an element.
T Dequeue()
{
T retval;
// Request the lock, and block until it is obtained.
Monitor::Enter(m_inputQueue);
try
{
// When the lock is obtained, dequeue an element.
retval = m_inputQueue->Dequeue();
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
return retval;
};
// Delete all elements that equal the given object.
int Remove(T qValue)
{
int removedCt = 0;
// Wait until the lock is available and lock the queue.
Monitor::Enter(m_inputQueue);
try
{
int counter = m_inputQueue->Count;
while (counter > 0)
// Check each element.
{
T elem = m_inputQueue->Dequeue();
if (!elem->Equals(qValue))
{
m_inputQueue->Enqueue(elem);
}
else
{
// Keep a count of items removed.
removedCt += 1;
}
counter = counter - 1;
}
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
return removedCt;
};
// Print all queue elements.
String^ PrintAllElements()
{
StringBuilder^ output = gcnew StringBuilder();
// Lock the queue.
Monitor::Enter(m_inputQueue);
try
{
for each ( T elem in m_inputQueue )
{
// Print the next element.
output->AppendLine(elem->ToString());
}
}
finally
{
// Ensure that the lock is released.
Monitor::Exit(m_inputQueue);
}
return output->ToString();
};
};
public ref class Example
{
private:
static SafeQueue<int>^ q = gcnew SafeQueue<int>();
static int threadsRunning = 0;
static array<array<int>^>^ results = gcnew array<array<int>^>(3);
static void ThreadProc(Object^ state)
{
DateTime finish = DateTime::Now.AddSeconds(10);
Random^ rand = gcnew Random();
array<int>^ result = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int threadNum = (int) state;
while (DateTime::Now < finish)
{
int what = rand->Next(250);
int how = rand->Next(100);
if (how < 16)
{
q->Enqueue(what);
result[(int)ThreadResultIndex::EnqueueCt] += 1;
}
else if (how < 32)
{
if (q->TryEnqueue(what))
{
result[(int)ThreadResultIndex::TryEnqueueSucceedCt] += 1;
}
else
{
result[(int)ThreadResultIndex::TryEnqueueFailCt] += 1;
}
}
else if (how < 48)
{
// Even a very small wait significantly increases the success
// rate of the conditional enqueue operation.
if (q->TryEnqueue(what, 10))
{
result[(int)ThreadResultIndex::TryEnqueueWaitSucceedCt] += 1;
}
else
{
result[(int)ThreadResultIndex::TryEnqueueWaitFailCt] += 1;
}
}
else if (how < 96)
{
result[(int)ThreadResultIndex::DequeueCt] += 1;
try
{
q->Dequeue();
}
catch (Exception^ ex)
{
result[(int)ThreadResultIndex::DequeueExCt] += 1;
}
}
else
{
result[(int)ThreadResultIndex::RemoveCt] += 1;
result[(int)ThreadResultIndex::RemovedCt] += q->Remove(what);
}
}
results[threadNum] = result;
if (0 == Interlocked::Decrement(threadsRunning))
{
StringBuilder^ sb = gcnew StringBuilder(
" Thread 1 Thread 2 Thread 3 Total\n");
for (int row = 0; row < 9; row++)
{
int total = 0;
sb->Append(titles[row]);
for(int col = 0; col < 3; col++)
{
sb->Append(String::Format("{0,9}", results[col][row]));
total += results[col][row];
}
sb->AppendLine(String::Format("{0,9}", total));
}
Console::WriteLine(sb->ToString());
}
};
static array<String^>^ titles = {
"Enqueue ",
"TryEnqueue succeeded ",
"TryEnqueue failed ",
"TryEnqueue(T, wait) succeeded ",
"TryEnqueue(T, wait) failed ",
"Dequeue attempts ",
"Dequeue exceptions ",
"Remove operations ",
"Queue elements removed "};
enum class ThreadResultIndex
{
EnqueueCt,
TryEnqueueSucceedCt,
TryEnqueueFailCt,
TryEnqueueWaitSucceedCt,
TryEnqueueWaitFailCt,
DequeueCt,
DequeueExCt,
RemoveCt,
RemovedCt
};
public:
static void Demo()
{
Console::WriteLine("Working...");
for(int i = 0; i < 3; i++)
{
Thread^ t = gcnew Thread(gcnew ParameterizedThreadStart(Example::ThreadProc));
t->Start(i);
Interlocked::Increment(threadsRunning);
}
};
};
void main()
{
Example::Demo();
}
/* This example produces output similar to the following:
Working...
Thread 1 Thread 2 Thread 3 Total
Enqueue 274718 513514 337895 1126127
TryEnqueue succeeded 274502 513516 337480 1125498
TryEnqueue failed 119 235 141 495
TryEnqueue(T, wait) succeeded 274552 513116 338532 1126200
TryEnqueue(T, wait) failed 0 1 0 1
Dequeue attempts 824038 1541866 1015006 3380910
Dequeue exceptions 12828 23416 14799 51043
Remove operations 68746 128218 84306 281270
Queue elements removed 11464 22024 14470 47958
Queue elements removed 2921 4690 2982 10593
*/
using System;
using System.Threading;
using System.Collections.Generic;
using System.Text;
class SafeQueue<T>
{
// A queue that is protected by Monitor.
private Queue<T> m_inputQueue = new Queue<T>();
// Lock the queue and add an element.
public void Enqueue(T qValue)
{
// Request the lock, and block until it is obtained.
Monitor.Enter(m_inputQueue);
try
{
// When the lock is obtained, add an element.
m_inputQueue.Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
}
// Try to add an element to the queue: Add the element to the queue
// only if the lock is immediately available.
public bool TryEnqueue(T qValue)
{
// Request the lock.
if (Monitor.TryEnter(m_inputQueue))
{
try
{
m_inputQueue.Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
return true;
}
else
{
return false;
}
}
// Try to add an element to the queue: Add the element to the queue
// only if the lock becomes available during the specified time
// interval.
public bool TryEnqueue(T qValue, int waitTime)
{
// Request the lock.
if (Monitor.TryEnter(m_inputQueue, waitTime))
{
try
{
m_inputQueue.Enqueue(qValue);
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
return true;
}
else
{
return false;
}
}
// Lock the queue and dequeue an element.
public T Dequeue()
{
T retval;
// Request the lock, and block until it is obtained.
Monitor.Enter(m_inputQueue);
try
{
// When the lock is obtained, dequeue an element.
retval = m_inputQueue.Dequeue();
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
return retval;
}
// Delete all elements that equal the given object.
public int Remove(T qValue)
{
int removedCt = 0;
// Wait until the lock is available and lock the queue.
Monitor.Enter(m_inputQueue);
try
{
int counter = m_inputQueue.Count;
while (counter > 0)
// Check each element.
{
T elem = m_inputQueue.Dequeue();
if (!elem.Equals(qValue))
{
m_inputQueue.Enqueue(elem);
}
else
{
// Keep a count of items removed.
removedCt += 1;
}
counter = counter - 1;
}
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
return removedCt;
}
// Print all queue elements.
public string PrintAllElements()
{
StringBuilder output = new StringBuilder();
// Lock the queue.
Monitor.Enter(m_inputQueue);
try
{
foreach( T elem in m_inputQueue )
{
// Print the next element.
output.AppendLine(elem.ToString());
}
}
finally
{
// Ensure that the lock is released.
Monitor.Exit(m_inputQueue);
}
return output.ToString();
}
}
public class Example
{
private static SafeQueue<int> q = new SafeQueue<int>();
private static int threadsRunning = 0;
private static int[][] results = new int[3][];
static void Main()
{
Console.WriteLine("Working...");
for(int i = 0; i < 3; i++)
{
Thread t = new Thread(ThreadProc);
t.Start(i);
Interlocked.Increment(ref threadsRunning);
}
}
private static void ThreadProc(object state)
{
DateTime finish = DateTime.Now.AddSeconds(10);
Random rand = new Random();
int[] result = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int threadNum = (int) state;
while (DateTime.Now < finish)
{
int what = rand.Next(250);
int how = rand.Next(100);
if (how < 16)
{
q.Enqueue(what);
result[(int)ThreadResultIndex.EnqueueCt] += 1;
}
else if (how < 32)
{
if (q.TryEnqueue(what))
{
result[(int)ThreadResultIndex.TryEnqueueSucceedCt] += 1;
}
else
{
result[(int)ThreadResultIndex.TryEnqueueFailCt] += 1;
}
}
else if (how < 48)
{
// Even a very small wait significantly increases the success
// rate of the conditional enqueue operation.
if (q.TryEnqueue(what, 10))
{
result[(int)ThreadResultIndex.TryEnqueueWaitSucceedCt] += 1;
}
else
{
result[(int)ThreadResultIndex.TryEnqueueWaitFailCt] += 1;
}
}
else if (how < 96)
{
result[(int)ThreadResultIndex.DequeueCt] += 1;
try
{
q.Dequeue();
}
catch
{
result[(int)ThreadResultIndex.DequeueExCt] += 1;
}
}
else
{
result[(int)ThreadResultIndex.RemoveCt] += 1;
result[(int)ThreadResultIndex.RemovedCt] += q.Remove(what);
}
}
results[threadNum] = result;
if (0 == Interlocked.Decrement(ref threadsRunning))
{
StringBuilder sb = new StringBuilder(
" Thread 1 Thread 2 Thread 3 Total\n");
for(int row = 0; row < 9; row++)
{
int total = 0;
sb.Append(titles[row]);
for(int col = 0; col < 3; col++)
{
sb.Append(String.Format("{0,9}", results[col][row]));
total += results[col][row];
}
sb.AppendLine(String.Format("{0,9}", total));
}
Console.WriteLine(sb.ToString());
}
}
private static string[] titles = {
"Enqueue ",
"TryEnqueue succeeded ",
"TryEnqueue failed ",
"TryEnqueue(T, wait) succeeded ",
"TryEnqueue(T, wait) failed ",
"Dequeue attempts ",
"Dequeue exceptions ",
"Remove operations ",
"Queue elements removed "};
private enum ThreadResultIndex
{
EnqueueCt,
TryEnqueueSucceedCt,
TryEnqueueFailCt,
TryEnqueueWaitSucceedCt,
TryEnqueueWaitFailCt,
DequeueCt,
DequeueExCt,
RemoveCt,
RemovedCt
};
}
/* This example produces output similar to the following:
Working...
Thread 1 Thread 2 Thread 3 Total
Enqueue 277382 515209 308464 1101055
TryEnqueue succeeded 276873 514621 308099 1099593
TryEnqueue failed 109 181 134 424
TryEnqueue(T, wait) succeeded 276913 514434 307607 1098954
TryEnqueue(T, wait) failed 2 0 0 2
Dequeue attempts 830980 1544081 924164 3299225
Dequeue exceptions 12102 21589 13539 47230
Remove operations 69550 129479 77351 276380
Queue elements removed 11957 22572 13043 47572
*/
Imports System.Threading
Imports System.Collections.Generic
Imports System.Text
Class SafeQueue(Of T)
' A queue that is protected by Monitor.
Private m_inputQueue As New Queue(Of T)
' Lock the queue and add an element.
Public Sub Enqueue(ByVal qValue As T)
' Request the lock, and block until it is obtained.
Monitor.Enter(m_inputQueue)
Try
' When the lock is obtained, add an element.
m_inputQueue.Enqueue(qValue)
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
End Sub
' Try to add an element to the queue: Add the element to the queue
' only if the lock is immediately available.
Public Function TryEnqueue(ByVal qValue As T) As Boolean
' Request the lock.
If Monitor.TryEnter(m_inputQueue) Then
Try
m_inputQueue.Enqueue(qValue)
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
Return True
Else
Return False
End If
End Function
' Try to add an element to the queue: Add the element to the queue
' only if the lock becomes available during the specified time
' interval.
Public Function TryEnqueue(ByVal qValue As T, ByVal waitTime As Integer) As Boolean
' Request the lock.
If Monitor.TryEnter(m_inputQueue, waitTime) Then
Try
m_inputQueue.Enqueue(qValue)
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
Return True
Else
Return False
End If
End Function
' Lock the queue and dequeue an element.
Public Function Dequeue() As T
Dim retval As T
' Request the lock, and block until it is obtained.
Monitor.Enter(m_inputQueue)
Try
' When the lock is obtained, dequeue an element.
retval = m_inputQueue.Dequeue()
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
Return retval
End Function
' Delete all elements that equal the given object.
Public Function Remove(ByVal qValue As T) As Integer
Dim removedCt As Integer = 0
' Wait until the lock is available and lock the queue.
Monitor.Enter(m_inputQueue)
Try
Dim counter As Integer = m_inputQueue.Count
While (counter > 0)
'Check each element.
Dim elem As T = m_inputQueue.Dequeue()
If Not elem.Equals(qValue) Then
m_inputQueue.Enqueue(elem)
Else
' Keep a count of items removed.
removedCt += 1
End If
counter = counter - 1
End While
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
Return removedCt
End Function
' Print all queue elements.
Public Function PrintAllElements() As String
Dim output As New StringBuilder()
'Lock the queue.
Monitor.Enter(m_inputQueue)
Try
For Each elem As T In m_inputQueue
' Print the next element.
output.AppendLine(elem.ToString())
Next
Finally
' Ensure that the lock is released.
Monitor.Exit(m_inputQueue)
End Try
Return output.ToString()
End Function
End Class
Public Class Example
Private Shared q As New SafeQueue(Of Integer)
Private Shared threadsRunning As Integer = 0
Private Shared results(2)() As Integer
Friend Shared Sub Main()
Console.WriteLine("Working...")
For i As Integer = 0 To 2
Dim t As New Thread(AddressOf ThreadProc)
t.Start(i)
Interlocked.Increment(threadsRunning)
Next i
End Sub
Private Shared Sub ThreadProc(ByVal state As Object)
Dim finish As DateTime = DateTime.Now.AddSeconds(10)
Dim rand As New Random()
Dim result() As Integer = { 0, 0, 0, 0, 0, 0, 0, 0, 0 }
Dim threadNum As Integer = CInt(state)
While (DateTime.Now < finish)
Dim what As Integer = rand.Next(250)
Dim how As Integer = rand.Next(100)
If how < 16 Then
q.Enqueue(what)
result(ThreadResultIndex.EnqueueCt) += 1
Else If how < 32 Then
If q.TryEnqueue(what)
result(ThreadResultIndex.TryEnqueueSucceedCt) += 1
Else
result(ThreadResultIndex.TryEnqueueFailCt) += 1
End If
Else If how < 48 Then
' Even a very small wait significantly increases the success
' rate of the conditional enqueue operation.
If q.TryEnqueue(what, 10)
result(ThreadResultIndex.TryEnqueueWaitSucceedCt) += 1
Else
result(ThreadResultIndex.TryEnqueueWaitFailCt) += 1
End If
Else If how < 96 Then
result(ThreadResultIndex.DequeueCt) += 1
Try
q.Dequeue()
Catch
result(ThreadResultIndex.DequeueExCt) += 1
End Try
Else
result(ThreadResultIndex.RemoveCt) += 1
result(ThreadResultIndex.RemovedCt) += q.Remove(what)
End If
End While
results(threadNum) = result
If 0 = Interlocked.Decrement(threadsRunning) Then
Dim sb As New StringBuilder( _
" Thread 1 Thread 2 Thread 3 Total" & vbLf)
For row As Integer = 0 To 8
Dim total As Integer = 0
sb.Append(titles(row))
For col As Integer = 0 To 2
sb.Append(String.Format("{0,9}", results(col)(row)))
total += results(col)(row)
Next col
sb.AppendLine(String.Format("{0,9}", total))
Next row
Console.WriteLine(sb.ToString())
End If
End Sub
Private Shared titles() As String = { _
"Enqueue ", _
"TryEnqueue succeeded ", _
"TryEnqueue failed ", _
"TryEnqueue(T, wait) succeeded ", _
"TryEnqueue(T, wait) failed ", _
"Dequeue attempts ", _
"Dequeue exceptions ", _
"Remove operations ", _
"Queue elements removed " _
}
Private Enum ThreadResultIndex
EnqueueCt
TryEnqueueSucceedCt
TryEnqueueFailCt
TryEnqueueWaitSucceedCt
TryEnqueueWaitFailCt
DequeueCt
DequeueExCt
RemoveCt
RemovedCt
End Enum
End Class
' This example produces output similar to the following:
'
'Working...
' Thread 1 Thread 2 Thread 3 Total
'Enqueue 294357 512164 302838 1109359
'TryEnqueue succeeded 294486 512403 303117 1110006
'TryEnqueue failed 108 234 127 469
'TryEnqueue(T, wait) succeeded 294259 512796 302556 1109611
'TryEnqueue(T, wait) failed 1 1 1 3
'Dequeue attempts 882266 1537993 907795 3328054
'Dequeue exceptions 12691 21474 13480 47645
'Remove operations 74059 128715 76187 278961
'Queue elements removed 12667 22606 13219 48492
Remarques
Permet Enter
d’acquérir l’objet Monitor passé en tant que paramètre. Si un autre thread a exécuté un Enter
sur l’objet mais n’a pas encore exécuté le thread correspondant Exit, le thread actuel se bloque jusqu’à ce que l’autre thread libère l’objet. Il est légal pour le même thread d’appeler Enter
plusieurs fois sans qu’il ne bloque . Toutefois, un nombre égal d’appels Exit
doit être appelé avant que d’autres threads en attente de l’objet débloquent.
Permet Monitor de verrouiller des objets (c’est-à-dire des types référence), et non des types valeur. Lorsque vous passez une variable de type valeur à Enter
, elle est boxée en tant qu’objet. Si vous passez la même variable à Enter
nouveau, elle est boxée en tant qu’objet distinct et le thread ne bloque pas. Dans ce cas, le code censé Monitor
protéger n’est pas protégé. En outre, lorsque vous passez la variable à Exit
, un autre objet distinct est créé. Étant donné que l’objet passé à Exit
est différent de l’objet passé à Enter
, Monitor
lève SynchronizationLockException. Pour plus d’informations, consultez la rubrique conceptuelle Moniteurs.
Interrupt peut interrompre les threads qui attendent d’entrer un Monitor
objet. Un ThreadInterruptedException sera jeté.
Utiliser un C# try
...finally
bloquer (Try
...Finally
en Visual Basic) pour vous assurer que vous relâchez le moniteur ou utilisez l’instruction C# lock
(SyncLock
instruction en Visual Basic), qui encapsule les méthodes et Exit les Enter éléments dans un try
...finally
Bloc.
Voir aussi
S’applique à
Enter(Object, Boolean)
Acquiert un verrou exclusif sur l'objet spécifié et définit de manière atomique une valeur qui indique si le verrou a été pris.
public:
static void Enter(System::Object ^ obj, bool % lockTaken);
public static void Enter (object obj, ref bool lockTaken);
static member Enter : obj * bool -> unit
Public Shared Sub Enter (obj As Object, ByRef lockTaken As Boolean)
Paramètres
- obj
- Object
Objet sur lequel attendre.
- lockTaken
- Boolean
Résultat de la tentative d'acquisition du verrou, passé par la référence. L'entrée doit avoir la valeur false
. La sortie a la valeur true
si un verrou est acquis ; sinon, elle a la valeur false
. La sortie est définie même si une exception se produit lors de la tentative d'acquisition du verrou.
Remarque Si aucune exception ne se produit, la sortie de cette méthode est toujours true
.
Exceptions
L’entrée de lockTaken
est true
.
Le paramètre obj
a la valeur null
.
Exemples
Le code suivant montre le modèle de base pour l’utilisation de la surcharge de Enter(Object, Boolean) méthode. Cette surcharge définit toujours la valeur de la variable passée au ref
paramètre (ByRef
en Visual Basic), lockTaken
même si la méthode lève une exception, de sorte que la valeur de la variable est un moyen fiable de tester si le verrou doit être libéré.
bool acquiredLock = false;
try
{
Monitor.Enter(lockObject, ref acquiredLock);
// Code that accesses resources that are protected by the lock.
}
finally
{
if (acquiredLock)
{
Monitor.Exit(lockObject);
}
}
Dim acquiredLock As Boolean = False
Try
Monitor.Enter(lockObject, acquiredLock)
' Code that accesses resources that are protected by the lock.
Finally
If acquiredLock Then
Monitor.Exit(lockObject)
End If
End Try
Remarques
Permet Enter
d’acquérir l’objet Monitor passé en tant que obj
paramètre. Si un autre thread a exécuté un Enter
sur l’objet mais n’a pas encore exécuté le thread correspondant Exit, le thread actuel se bloque jusqu’à ce que l’autre thread libère l’objet. Il est légal pour le même thread d’appeler Enter
plusieurs fois sans qu’il ne bloque . Toutefois, un nombre égal d’appels Exit
doit être appelé avant que d’autres threads en attente de l’objet débloquent.
Si le verrou n’a pas été pris parce qu’une exception a été levée, la variable spécifiée pour le lockTaken
paramètre se false
termine après la fin de cette méthode. Cela permet au programme de déterminer, dans tous les cas, s’il est nécessaire de libérer le verrou. Si cette méthode retourne sans lever d’exception, la variable spécifiée pour le lockTaken
paramètre est toujours true
, et il n’est pas nécessaire de la tester.
Permet Monitor de verrouiller des objets (c’est-à-dire des types référence), et non des types valeur. Lorsque vous passez une variable de type valeur à Enter
, elle est boxée en tant qu’objet. Si vous passez la même variable à Enter
nouveau, elle est boxée en tant qu’objet distinct et le thread ne bloque pas. Dans ce cas, le code censé Monitor
protéger n’est pas protégé. En outre, lorsque vous passez la variable à Exit
, un autre objet distinct est créé. Étant donné que l’objet passé à Exit
est différent de l’objet passé à Enter
, Monitor
lève SynchronizationLockException. Pour plus d’informations, consultez la rubrique conceptuelle Moniteurs.
Interrupt peut interrompre les threads qui attendent d’entrer un Monitor
objet. Un ThreadInterruptedException sera jeté.