Java program compares the execution time to ArrayList and LinkedList

package taesik; import java.util.ArrayList; import java.util.LinkedList; import java.util.Random; public class Assignment4OUTLINE { static Bar211 bar; static int howManyTests=18000; //Change this number if it takes too long or too short. static ArrayList<String> AL = new ArrayList<>(); static LinkedList<String> LL = new LinkedList<>(); static double TimeAdd_ArrayList; // in milisecond static double TimeAdd_LinkedList; static double TimeSearch_ArrayList; static double TimeSearch_LinkedList; static double TimeRemove_ArrayList; static double TimeRemove_LinkedList; static double startTime, endTime, totalTime; static Random rand = new Random(); static void add(){ int index; String value; for (int i=0; i<howManyTests; i++){ // generate an index within ArrayList size // generate a value String of length 10 // ADD 1) ArrayList startTime = System.currentTimeMillis(); //add the value to ArrayList endTime = System.currentTimeMillis(); TimeAdd_ArrayList += endTime - startTime; // accumulate // call graphic class to draw a bar bar.setTimeAddAL(TimeAdd_ArrayList); //ADD 2) LinkedList startTime = System.currentTimeMillis(); //add the value to LinkedList endTime = System.currentTimeMillis(); TimeAdd_LinkedList += endTime - startTime; // call graphic class to draw a bar bar.setTimeAddLL(TimeAdd_LinkedList); } // Print result (Text version) System.out.println("ADD: "); System.out.println("ArrayList: "+TimeAdd_ArrayList/1000.0 + " Sec"); System.out.println("LinkedList: "+TimeAdd_LinkedList/1000.0+ " Sec"); // evaluate which one is faster } static void search(){ int index; String value; for (int i=0; i<howManyTests; i++){ // generate a value String of length 10 // SEARCH 1) ArrayList startTime = System.currentTimeMillis(); // find index endTime = System.currentTimeMillis(); TimeSearch_ArrayList += endTime - startTime; // call graphic class to draw a bar bar.setTimeSearchAL(TimeSearch_ArrayList); // SEARCH 2) LinkedList startTime = System.currentTimeMillis(); // find index endTime = System.currentTimeMillis(); TimeSearch_LinkedList += endTime - startTime; // call graphic class to draw a bar bar.setTimeSearchLL(TimeSearch_LinkedList); } // Print result (Text version) // evaluate which one is faster } static void remove(){ int index; String value; for (int i=0; i<howManyTests; i++){ // generate a value String of length 10; // REMOVE 1) ArrayList startTime = System.currentTimeMillis(); // remove the value endTime = System.currentTimeMillis(); TimeRemove_ArrayList += endTime - startTime; // call graphic class to draw a bar bar.setTimeRemoveAL(TimeRemove_ArrayList); // REMOVE 2) LinkedList startTime = System.currentTimeMillis(); // remove the value endTime = System.currentTimeMillis(); TimeRemove_LinkedList += endTime - startTime; // call graphic class to draw a bar bar.setTimeRemoveLL(TimeRemove_LinkedList); } // Print result (Text version) // evaluate which one is faster } public static String nextWord(int length) { String s=""; for (int i=1;i<=length;i++) { int r=rand.nextInt('Z'-'A'+ 1) + 'A'; char c= (char) r; s+=c; } return s; } //main method calling methods, and creating GUI as well as bars on GUI public static void main(String[] args) { bar = new Bar211("your name", howManyTests); // if your first name is "your" and your last name is "name", use this statement as is. // Otherwise, change it to your real name. add(); search(); remove(); } }