In some situations, we will have to wait for the finalization of a thread. For example, we may have a program that will begin initializing the resources it needs before proceeding with the rest of the execution. We can run the initialization tasks as threads and wait for its finalization before continuing with the rest of the program. For this purpose, we can use the join() method of the Thread class. When we call this method using a thread object, it suspends the execution of the calling thread until the object called finishes its execution. In this article, we are going to explore Join method of thread class.
I will Join You in Heaven
I can rephrase this section heading as “I will wait until you die.” That’s right. A thread can wait for another thread to die (or terminate).
Suppose there are two threads, t1 and t2. If the thread t1 executes t2.join(), thread t1 starts waiting until thread t2 is terminated. In other words, the call t2.join() blocks until t2 terminates. Using the join() method in a program is useful if one of the threads cannot proceed until another thread has finished executing.
An example where you want to print a message on the standard output when the program has finished executing. The message to print is “Printing Done.”
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