It's the other way round actually. Arraylists do not have fixed size and can increase or decrease in size as needed. On the other hand, Arrays are fixed from when they are declared; they have a particular size that number of elements cannot go beyond.
An arraylist in Java is a class that is part of a Java collection framework(java.util) that can have variable sizes and only store objects, not primitive data like strings or integers. An array is a data structure in Java and can store both primitive data and objects, while having a fixed size at declaration.
Answer: Most of the time its caused by a virus and the virus takes the chance when your computer resets so look for a virus if that's not it maybe its power failure check if its in a window folder or just use a antivirus.
