ExecutorCoroutineDispatcher class Correct Implementation

    class dispatch : ExecutorCoroutineDispatcher() {
        private val services = Executors.newCachedThreadPool()
    
        override val executor: Executor
            get() = services
    
        override fun dispatch(context: CoroutineContext, block: Runnable) {
            println("dispatch ")
            if(this.isDispatchNeeded(context)){
                executor.execute(block)
            }else{
                Dispatchers.Unconfined.dispatch(context , block) 
            }
        }
    
        override fun isDispatchNeeded(context: CoroutineContext): Boolean {
            println("isDispatchedNeeded ")
 // Implement your custom logic here to determine if dispatch is needed
            return false // assuming yield() call in loop so return false 
        }
    
        override fun close() {
            services.shutdown()
        }
    }
        fun main() {
            runBlocking {
                launch(dispatch()) {
                    for (i in 1..3) {
                        println("start")
                        yield()// dispatch() call in loop may cause stackOverFlowError
                        println("end")
                    }
                }
        
                launch(dispatch()) {
                    println("some suspend function")
                    work() // some suspend work 
                }
            }
        }
suspend fun work() {
    delay(1000) // Simulating some suspend work
}

I read this dispatch(). i could not understand what is better way to implement this function according dispatch() documentation . as they talk about

This method should guarantee that the given block will be eventually invoked, otherwise the system may reach a deadlock state and never leave it.

This method must not immediately call block. Doing so may result in StackOverflowError when dispatch is invoked repeatedly, for example when yield is called in a loop. In order to execute a block in place, it is required to return false from isDispatchNeeded and delegate the dispatch implementation to Dispatchers.Unconfined.dispatch in such cases. To support this, the coroutines machinery ensures in-place execution and forms an event-loop to avoid unbound recursion.

---> in my code when there is yield() in loop then it isDispatchNeeded return false and in dispatch use Unconfined Dispatcher as above in documentation to avoid stackoverflowerror but in documentation how can i handle when we need to call block[runnable] immediately to avoid deadlock.

please anyone Correct my code that correctly handles dispatching of coroutines, considering whether dispatch() called in loop or not and should ensureEnsure proper error handling and exception management in dispatch() , isDispatchedNeeded() that handle issues like deadlock or StackOverflowError etc ?

Question is pretty confusing to me. You say you would like to implement a dispatcher based on an executor, but then you don't want to dispatch, but to call the runnable directly (?). Sounds quite contradicting.

1. There is an existing implementation and it's probably the best to use it: executor.asCoroutineDispatcher().
2. If this is for learning or you have some additional needs, then your current implementation is mostly fine, you just need to return true from isDispatchNeeded.
3. If you really need to execute directly, then the documentation you cited answers this directly:

In order to execute a block in place, it is required to return false from isDispatchNeeded and delegate the dispatch implementation to Dispatchers.Unconfined.dispatch in such cases

override fun dispatch(context: CoroutineContext, block: Runnable) = Dispatchers.Unconfined.dispatch(context, block)