Java Arrays are used to store multiple values in a single variable, instead of declaring separate variables for each value. long array[] = new long[5]; Arrays.fill(array, 30); The method also has several alternatives which set a range of an array to a particular value: An array is a data structure/container/object that stores a fixed-size sequential collection of elements of the same type. In Java we can't use Length field like we used to one-dimensional arrays. Java Array Length Examples. An Array in Java can hold arbitrary number of elements, depending on how the array object was created. First, you need to know that the output of the Length field in multidimensional arrays is the number of rows.I mean when you have below array. The number of elements in the array during declaration is called the size or length of the array. So simply writing a few lines of code solves this problem. The java.util.Arrays class has several methods named fill() which accept different types of arguments and fill the whole array with the same value:. Syntax So here’s a loop: int i=0; while (i