Avoid ConcurrentModificationException while looping over Java ArrayList?

Apart from the NullPointerException and ClassNotFoundException, ConcurrentModificationException is another nightmare for Java developers. What makes this error tricky is the word concurrent, which always mislead Java programmers that this exception is coming because multiple threads are trying to modify the collection at the same time. Then begins the hunting, they spent countless hours to find the code which has the probability of concurrent modification. While in reality ConcurrentModficationException can also come on the single threaded environment. To give you an example, just loop over a list using for loop and try to remove one element, you will get the ConcurrentModificatoinExcetpion? Why? because you broke the rule of not modifying a Collection during iteration.

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