Clerk Class

.NET Framework (current version)

Writes records of transactional actions to a log.

Namespace: System.EnterpriseServices.CompensatingResourceManager
Assembly: System.EnterpriseServices (in System.EnterpriseServices.dll)

Inheritance Hierarchy

System::Object
System.EnterpriseServices.CompensatingResourceManager::Clerk

Syntax

C++

public ref class Clerk sealed

Constructors

	Name	Description
	Clerk(String^, String^, CompensatorOptions)	Initializes a new instance of the Clerk class.
	Clerk(Type^, String^, CompensatorOptions)	Initializes a new instance of the Clerk class.

Properties

	Name	Description
	LogRecordCount	Gets the number of log records.
	TransactionUOW	Gets a value representing the transaction unit of work (UOW).

Methods

	Name	Description
	Equals(Object^)	Determines whether the specified object is equal to the current object.(Inherited from Object.)
	Finalize()	Frees the resources of the current Clerk before it is reclaimed by the garbage collector.(Overrides Object::Finalize().)
	ForceLog()	Forces all log records to disk.
	ForceTransactionToAbort()	Performs an immediate abort call on the transaction.
	ForgetLogRecord()	Does not deliver the last log record that was written by this instance of this interface.
	GetHashCode()	Serves as the default hash function. (Inherited from Object.)
	GetType()	Gets the Type of the current instance.(Inherited from Object.)
	ToString()	Returns a string that represents the current object.(Inherited from Object.)
	WriteLogRecord(Object^)	Writes unstructured log records to the log.

Remarks

Each clerk is associated with a compensator, which is called back to perform actions during the two-phase commit of the transaction.

Examples

The following code example demonstrates the use of this class.

C++

// A CRM Worker
[Transaction]
public ref class Account : public ServicedComponent
{

    // A data member for the account file name.
private:
    String^ filenameValue;

public:
    property String^ Filename
    {
        String^ get()
        {
            return filenameValue;
        }
        void set( String^ value )
        {
            filenameValue = value;
        }
    }

    // A boolean data member that determines whether to commit or abort the 
    // transaction.
private:
    bool allowCommitValue;

public:
    property bool AllowCommit
    {
        bool get()
        {
            return allowCommitValue;
        }
        void set( bool value )
        {
            allowCommitValue = value;
        }
    }

    // Debit the account, 
public:
    void DebitAccount(int amount)
    {

        // Create a new clerk using the AccountCompensator class.
        Clerk^ clerk = gcnew Clerk(AccountCompensator::typeid,
            "An account transaction compensator", CompensatorOptions::AllPhases);

        // Create a record of previous account status, and deliver it to the
        // clerk.
        int balance = ReadAccountBalance(Filename);

        array<Object^>^ record = gcnew array<Object^>(2);
        record[0] = Filename;
        record[1] = balance;

        clerk->WriteLogRecord(record);
        clerk->ForceLog();

        // Perform the transaction
        balance -= amount;

        Console::WriteLine("{0}: {1}", Filename, balance);

        WriteAccountBalance(Filename, balance);

        // Commit or abort the transaction 
        if (AllowCommit)
        {
            ContextUtil::SetComplete();
        }
        else
        {
            ContextUtil::SetAbort();
        }

    }

};

The following code example demonstrates the corresponding Compensator class.

C++

#using "System.EnterpriseServices.dll"

using namespace System;

[assembly: System::Reflection::AssemblyKeyFile("CrmServer.key")];

int main ()
{

    // Create a new account object. The object is created in a COM+ server application.
    Account^ account = gcnew Account();

    // Transactionally debit the account.
    try
    {
        account->Filename = System::IO::Path::GetFullPath("JohnDoe");
        account->AllowCommit = true;
        account->DebitAccount(3);
    }
    finally
    {
        delete account;
    }

}

Version Information

.NET Framework
Available since 1.1

Thread Safety

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.