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Threading

We’re quite familiar with the idea of writing a program that follows a specific sequence of steps as outlined in, say, a main() function. A Thread is also a series of steps with a beginning, a middle, and an end. A thread’s sequence, however, can run independently of the main program. In fact, we can launch any number of threads at one time and they will all run concurrently. Visit the Java site for a more involved explanation.

This is incredibly useful when it comes to data mining, as we can have separate threads retrieving different pieces of information from the network. If one gets stuck or has an error, the entire program won’t grind to a halt, since the error only stops that individual thread. To create independent, asynchronous threads, we simply extend the Thread class.