How can the parent thread wait for the child thread to finish?

How can the parent thread wait for the child thread to finish?

In java Thread join method is used, so that main or parent thread can wait for its child thread to finish its execution and die. In below thread program, main () method in Sample class is the main thread and it is creating and starting a child thread.

Which method is used to make thread to wait for all child threads?

Explanation: By calling sleep() within main(), with long enough delay to ensure that all child threads terminate prior to the main thread. 2.

Which function helps a main thread to wait for the complete execution of it’s daughter thread?

join() function
The output shows that the child thread executes the run() method and the main thread waits for the childs execution to complete. This is because of the join() function, which makes the main thread wait for the child to finish.

Does child threads still execute after even if their parent thread dies or terminates?

Because if parent thread dies or terminates then child thread should also die or terminate.

Can main thread exit before child?

As long as the main-method thread or any other user thread remains alive, your application will continue to execute. In your case, the threads are user threads and hence are allowed to complete before the main thread exits.

Which thread will be executed first if two threads have same priority?

Q) Which thread will be executed first if two threads have same priority. They will fall in starvation and none will be executed.

What is it called when child thread is running and parent thread is killed?

if ‘parent’ is the last non-daemon thread running (and thus ‘child1′ and child2’ threads are daemon threads), then when ‘parent’ dies, the JVM starts to shutdown, so the ‘child’ threads would also die.

What happens if a thread dies?

A thread dies naturally when its run() method exits normally. For example, the while loop in this method is a finite loop–it will iterate 100 times and then exit. A thread with this run() method will die naturally after the loop and the run() method completes. Thread myThread = new MyThreadClass(); myThread.

What will happen if two thread of the same priority?

Explanation: In cases where two or more thread with same priority are competing for CPU cycles, different operating system handle this situation differently. Explanation: Thread exist in several states, a thread can be running, suspended, blocked, terminated & ready to run.

Why is HashMap not thread safe?

HashMap is non-synchronized. It is not thread-safe and can’t be shared between many threads without proper synchronization code whereas Hashtable is synchronized. HashMap allows one null key and multiple null values whereas Hashtable doesn’t allow any null key or value.

What does wait until child threads are completed mean?

A synchronization aid that allows one or more threads to wait until a set of operations being performed in other threads completes.

What happens when one of child threads gets blocked?

After each child thread finishes their tasks, the main thread proceeds. The code I have written is working in most of the time. However, in case one of child thread gets blocked, the main thread has to wait for ever. As it is not happening frequently, I am kind of OK as of now. But I am looking for a better solution

What is an example of waiting for a thread to finish?

For example, if we need the current thread to wait for another N threads to finish their execution, we can initialize the latch using N:

How does The ExecutorService framework work in multiple threads?

The ExecutorService framework makes it easy to process tasks in multiple threads. We’re going to exemplify some scenarios in which we wait for threads to finish their execution. Also, we’ll show how to gracefully shutdown an ExecutorService and wait for already running threads to finish their execution.