If we want to submit tasks concurrently using threads then java.util.concurrent is good. The java.util.concurrent package (framework) is awesome for concurrent threading concept. If we want to control the maximun number of threads for any schedular task then ExcecutorService is nice to use to execute our tasks. we need to submit runnable object to executor service or we can also submit callable object to executor service. The difference between runnable and callable is runnable object doesn’t return but callable object return status. we can also track the status of executing tasks with CompletionService.
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