Common Runtime Exceptions

StackOverflowError is caused by exhausting the per-thread call stack through unbounded recursion, while OutOfMemoryError is caused by exhausting the shared JVM heap through memory leaks or large data.

ClassCastException occurs when you cast an object to a type it is not, commonly from invalid downcasts, raw-type heap pollution, or toArray() misuse, and is prevented by instanceof checks and proper generics.

IllegalArgumentException means the input is wrong (fix the argument), while IllegalStateException means the object's state is wrong (call at the right time), and the decision test is whether different arguments would fix the problem.

NoSuchElementException is thrown when asking for an element that does not exist, and is prevented by checking hasNext() before next(), using orElseThrow() instead of get(), and using poll()/peek() instead of remove()/element().