[Idea] Changing the use of synchronized in the getBinder method of DefaultBinderFactory class for virtual threads

[ferblaca]

The getBinder method in the DefaultBinderFactory class is marked as synchronized. However, the use of synchronized can be detrimental to performance when using Virtual Threads in Java, as it can introduce deadlocks that negatively affect concurrency and performance.

The getBinder method can be invoked multiple times during the life cycle of the application:

• During initialisation: When the application starts and configures the different message channels.
• At runtime: Every time a new binder is needed for a specific message channel.

So it would be nice to replace synchronized with a more suitable concurrency mechanism, like ReentrantLock.

If you think it's right, we can contribute it.

[ferblaca]

We have created the PR #3005 with the change I was talking about so that, if you think it makes sense, we can speed up the change.