Default Values

When an array is made by just providing a size, its elements are initialized to some default value.

For primitive types like int and double, each element will be initialized to 0.

void main() {
int[] digits = new int[10];
// 0
System.out.println(digits[0]);

double[] readings = new double[5];
// 0.0
System.out.println(readings[0]);
}

For boolean, each element will be initialized to false.¹

void main() {
boolean[] pokedex = new boolean[10];
// false
System.out.println(pokedex[0]);
}

And for every non-primitive type, which is every single type including the boxed primitives, the default value will be null.

void main() {
String[] names = new String[10];
// null
System.out.println(names[0]);

Integer[] scores = new Integer[26];
// null
System.out.println(scores[0]);
}