We love to work with Arrays because they are simple yet very powerful data structure in Java Language. It is also very intuitive and easy to use. If our needs does not require too much dynamic sizes, then arrays are just fine. But the first problem we encounter in working with arrays is how to fill it with initial values. Specially if the size of an array is created through a variable - meaning variable size that we don't know initially. And say we need to initialize the entire thing with a specific value, or only a portion of the array. The Arrays.fill() method is a good fit for this need. In this post we try to explore how to use Java Arrays.fill() method in different scenarios.