mfc, Are collection methods like GetSize thread safe?

1. General thread question - Thread safe object properties & methods?

2. Implementing thread safe Queue collection object

Hi,

I've been reading the online documentation for the System.Collections.Queue 
object on how to implement a threadsafe Queue object. 

I understand the basics, by using the wrapper returned by Synchronised 
method, but I'm not sure how to implement it between 2 threads. Has anyone 
got any suggestions or examples?

Thanks
Macca

3. Thread-safe enumeration thru collection? - CSharp/C#

4. Problem with making collection classes thread-safe

Sander Verhagen wrote:
> If (in an extreme case) thread 2 clears my collection, between
> GetStartPosition and GetNext calls of thread 1... thread 1 will be
> 'screwed', won't it?
> 
> The only way I see to prevent this really is to have these threads call
> lock/unlock methods. But I was just trying to keep all the locking private
> and thus transparent. :-(
> Any smart solutions?

Use enumeration, user calls your EnumItems function and provides it's 
own EnumItemsProc function. Synchronization is handled in EnumItems.

5. Thread-safe initialization of a mutex, was Thread-safe initialization of a function static

6. Making a base class' methods thread safe

I am creating several data access objects that all derive from a base class 
which implements the web service access functionality.

For example (fake code):
<code>
public class DAOBase
{
    protected List<TType> Search<TType>(string nameHint)
    {
        //  code to login to web service session, execute search
        //  and return the result.
        return new List<TType>();
    }
}

public class CustomerDAO : DAOBase
{
    public List<Customer> GetCustomer(string name)
    {
        return base.Search<Customer>(name);
    }
}

public class OrderDAO : DAOBase
{
    public List<Order> GetCustomerOrders(string name)
    {
        //  some code that will execute a search using the DAOBase
        //  Search method
        return null;
    }
}
</code>

The web service access exposed in DAOBase is session based and I can only 
have one session at a time.  In other words, I can't run two searches at the 
same time, they must be synchronous.
Once I've logged in (expensive operation) I want to reuse the same session 
for all subsequent requests.

I'm thinking of the different ways that I can accomplish this.  One idea is 
to refactor my code so that my web service functionality is in a new 
Singleton class, then the base class would have an instance of this 
singleton.  This way I could keep my session alive in the singleton and all 
concrete objects would access the singleton through the base class.

This would give me thread safety, or, more accurately it won't prevent two 
web service requests from being invoked on top of each other.  If this 
happens, the session will be killed. (bad)

I need to implement a queue to handle the web service request(s) from the 
various concrete DAO classes, most likely using the command pattern and 
wrapping all request in an object that can be enqueued.

So that is my first and only real idea to solve the issue.  Another idea 
that is fluttering around in my head is to keep the web service access in 
the base class but make the methods static.  This will give me the single 
session shared with all concrete objects but introduces thread safety issues 
(I think).

I would really like to hear what any of you think, before I start modifying 
(and breaking) my code all over the place I thought I would ask first to see 
if I'm on the right track.

Thanks for any input,
Steve

7. Thread-safe methods... - CSharp/C#

8. can an instance method be thread safe

If an instance method does not alter the containing class or any arguments of 
a referenced type is it thread safe?

public void GetSomething() {
     return new Something(this.Name);
}
public string Name;

Thanks,

Mike