public class CopyArray { CopyArray(){}; double[] originalArry ={1,2,3,4}; //stores original array void addToArray(double[] array, double s) { double[] tempArray = new double[array.length+1]; System.arraycopy(array, 0, tempArray, 0, array.length); tempArray[tempArray.length - 1] = s; originalArry =tempArray; //print out new array for(double d :originalArry ) System.out.println(d); } void addToArrayViaLoop(double[] array, double s) { double[] tempArray = new double[array.length+1]; for(int i =0;i<(tempArray.length-1);i++) tempArray[i] =array[i]; tempArray[tempArray.length-1] = s; originalArry = tempArray; for(double d : originalArry ) System.out.println("loop D "+d); } public static void main(String args[]){ double[] originalArray= {1,2,3,4 }; CopyArray c = new CopyArray(); // c.addToArray(originalArray, 5); c.addToArrayViaLoop(originalArray, 11); } }