Start Performance Testing - Array vs. ArrayList

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public class Array_PerformanceTest{
    public static void main(String args[])throws java.io.FileNotFoundException,InterruptedException{
        final int arraySize=Integer.parseInt(args[0]);
        int testArray[]=new int[arraySize];
        System.out.printf("All arrays use size: %,d",arraySize);
        System.out.println("                                hr: m: s:  ms");
        long time=System.currentTimeMillis();
        for(int index=0;index<arraySize;index++)
             testArray[index]=index;
        System.out.printf("Initializing array time: %20s\n",(getTime(System.currentTimeMillis()-time)));    
        time=System.currentTimeMillis();
        int result=sequentialSearch(testArray,arraySize-1);
        System.out.printf(" Sequential search time: %20s\n",(getTime(System.currentTimeMillis()-time)));
       

        time=System.currentTimeMillis();
        binarySearch(testArray,arraySize-1);
        System.out.printf("     Binary search time: %20s\n",(getTime(System.currentTimeMillis()-time)));
       
        java.util.Random rand=new java.util.Random();
       
        for(int index=0;index<arraySize;index++)
             testArray[index]=rand.nextInt(arraySize);
       
        time=System.currentTimeMillis();
        selectionSort(testArray);
        System.out.printf("    Selection sort time: %20s\n",(getTime(System.currentTimeMillis()-time)));
       
        java.util.ArrayList<String> list = new java.util.ArrayList<String>(arraySize);
        time=System.currentTimeMillis();
        for(int index=0;index<arraySize;index++)
               list.add(0, "Mary"+rand.nextInt(arraySize));
        System.out.printf("    Arraylist fill time: %20s\n",(getTime(System.currentTimeMillis()-time)));
       
        System.out.println();   

    }

    private static int sequentialSearch(int[] array, int value){
        int index,element;
        boolean found;  // Flag indicating search results
        index = 0;
        element = -1;
        found = false;
        while (!found && index < array.length) {
            if (array[index] == value) {
                found = true;     // Indicate the value is found.
                element = index;  // Save the subscript of the value.
            }
            index++;
        }
        return element;
    }

    private static void selectionSort(int[] array){
        int startScan, index, minIndex, minValue;
        for (startScan = 0; startScan < (array.length-1); startScan++) {
            minIndex = startScan;
            minValue = array[startScan];
            for(index = startScan + 1; index < array.length; index++) {
                if (array[index] < minValue) {
                    minValue = array[index];
                    minIndex = index;
                }
            }
            array[minIndex] = array[startScan];
            array[startScan] = minValue;
        }
    }

    private static int binarySearch(int[] array, int value){
        int first,last,middle,position;
        boolean found;   // Flag
        first = 0;
        last = array.length - 1;
        position = -1;
        found = false;

        while (!found && first <= last) {
            middle = (first + last) / 2;    // Calculate mid point
            if (array[middle] == value) {
                found = true;
                position = middle;
            }
            else if (array[middle] > value) // If value is in lower half
                last = middle - 1;
            else
                first = middle + 1;          // If value is in upper half
        }
        return position;
    }
   
    private static String getTime(long millis){
            long second = (millis / 1000) % 60;
            long minute = (millis / (1000 * 60)) % 60;
            long hour = (millis / (1000 * 60 * 60)) % 24;
            return String.format("%02d:%02d:%02d:%04d", hour, minute, second, millis);
    }
}