You could also try this.
public static int[] addOneIntToArray(int[] initialArray , int newValue) {
int[] newArray = new int[initialArray.length + 1];
for (int index = 0; index < initialArray.length; index++) {
newArray[index] = initialArray[index];
}
newArray[newArray.length - 1] = newValue;
return newArray;
}